Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months, and (2) has been subject to such filing requirements for the past 90 days.

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, or a non-accelerated filer. See definition of “accelerated filer and large accelerated filer” in Rule 12b-2 of the Exchange Act.

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).

          As of February 2,May 5, 2006, there were 21,990,20922,089,627 shares of the Registrant’s Common Stock, par value $.01 per share, outstanding.

          The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles of the United States of America for interim financial information and the instructions to Form 10-Q. Accordingly, they do not include all of the information and disclosures required by generally accepted accounting principles for complete financial statements. In the opinion of management, all adjustments (consisting of normal recurring items) considered necessary for fair presentation have been included. Operating results for the period ended January 1,April 2, 2006 are not necessarily indicative of the results that may be expected for the fiscal year ending September 30, 2006. Inter-company accounts and transactions have been eliminated in consolidation. For further information, refer to the consolidated financial statements and footnotes thereto included in Argon ST, Inc.’s Annual Report on Form 10-K for the fiscal year ended September 30, 2005. Reclassifications are made to the prior year financial statements when appropriate, to conform to the current year presentation.

          Argon ST maintains a September 30 fiscal year-end for annual financial reporting purposes. Argon ST presents its interim periods ending on the Sunday closest to the end of the month for each quarter consistent with labor and billing cycles. As a result, each quarter of each year may contain more or less days than other quarters of the year. Management does not believe that this practice has a material effect on quarterly results or on the comparison of such results.

          Argon ST records contract revenues and costs of operations for interim reporting purposes based on annual targeted indirect rates. At year-end, the revenues and costs are adjusted for actual indirect rates. During the Company’s interim reporting periods, variances may accumulate between the actual indirect rates and the annual targeted rates. Timing-related indirect spending variances are not applied to contract costs, research and development, and general and administrative expenses, but are included in unbilled receivables during these interim reporting periods. These rates are reviewed regularly, and the Company records adjustments for any material, permanent variances in the period they become determinable.

          Argon ST’s accounting policy for recording indirect rate variances is based on management’s belief that variances accumulated during interim reporting periods will be absorbed by management actions to control costs during the remainder of the year. The Company considers the rate variance to be unfavorable when the actual indirect rates are greater than the Company’s annual targeted rates. During interim reporting periods, unfavorable rate variances are recorded as reductions to operating expenses and increases to unbilled receivables. Favorable rate variances are recorded as increases to operating expenses and decreases to unbilled receivables. At January 1, 2006, the unfavorable rate variance approximated the Company’s planned variance for the period.

          If the Company anticipates that actual contract activities will be different than planned levels, there are alternatives the Company can utilize to absorb the variance: the Company can adjust planned indirect spending during the year, modify its billing rates to its customers, or record adjustments to expense based on estimates of future contract activities.

          If the Company’s rate variance is unfavorable, the modification of the Company’s indirect rates will likely increase revenue and operating expenses. Profit percentages on fixed-price contracts will generally decline as a result of an increase to indirect costs unless compensating savings can be achieved in the direct costs to complete the projects. Profit percentages on cost reimbursement contracts will generally decline as a percentage of total costs as a result of an increase in indirect costs even if the cost increase is funded by the customer. If the Company’s rate variance is favorable, the modification of the Company’s indirect rates will decrease revenue and operating expenses. In this event, profit percentages on fixed-price contracts will generally increase. Profit percentages on cost-reimbursable contracts will generally be unaffected as a result of any reduction to indirect costs, due to the fact that programs will typically expend all of the funds available. Any impact on operating income, however, will depend on a number of other factors, including mix of contract types, contract terms and anticipated performance on specific contracts.

          Basic earnings per share is computed using the weighted average number of common shares outstanding during each period. Diluted earnings per share is computed using the weighted average number of common and common equivalent shares outstanding during each period. The following summary is presented for the fiscal quarters ended January 1, 2006 and January 2, 2005:periods indicated.

          As of January 1,April 2, 2006, there was $5,957,000$6,280,000 of total unrecognized compensation cost related to nonvested share-based compensation arrangements. This cost is expected to be fully amortized in five years, with half of the total amortization cost being recognized within the next 24 months.

          During the fiscal quartersix months ended January 1,April 2, 2006, the Company granted stock options to purchase 484,350527,300 shares of common stock at a weighted-average exercise price of $29.46$29.48 per share. The Binomial weighted-average fair value of the options granted during the fiscal quartersix months ended January 1,April 2, 2006 was $14.57$13.28 per share. 409,350 ofOf these options, 452,300 vest at the rate of 20% per year over five years from the date of grant and 75,000 of these options vest in full in one year after the date of grant. All of the options expire ten years from the grant date. For the six months ended April 2, 2006, the weighted average closing price was $29.30 per share.

The previously disclosed pro forma effects of recognizing the estimated fair value of stock-based employee compensation, which historically was calculated using the Black-Scholes pricing model, for the fiscal quarterthree and six months ended January 2,April 3, 2005 are presented below.

          Of the purchase price, $1,066,000 was allocated to intangibles related to customer relationships and will be amortized over three years. In addition, $6,348,000 was allocated to goodwill, none of which is deductible for tax purposes. Pursuant to the requirements of SFAS No. 141, the effect of the acquisition did not meet the criteria of a material and significant acquisition, and therefore, pro forma disclosures are not presented.

     The following table summarizesProDesign Solutions, LLC

          On February 13, 2006, the preliminary estimated fair valueCompany acquired certain assets of the assets acquiredProDesign Solutions, LLC (“ProDesign”). ProDesign, based in Sarasota, Florida, provides a wide array of industrial design services including ruggedized electronic enclosures, electro-mechanical engineering, software/firmware engineering, and the liabilities assumed at the date of acquisition.rapid prototyping, with extensive experience in working with composite materials for weight savings. The Company has obtained third party valuationspaid $1,750,000 in cash and assumed liabilities of certain tangible$66,000 related to a note payable and intangible assets acquired from Radix.

          At April 2, 2006, the Company had $191,000 on deposit at least annually to determine if there has been any impairment to its value.

          On December 16, 2005, the Company completed itsa public offering of common stock at $29.00 per share. In the offering, the Company sold 1,725,000 shares. Selling stockholders sold an additional 920,000 shares, including 345,000 shares sold pursuant to an over-allotment option exercised by the underwriters. Proceeds to the Company from the offering were $46,768,000, net of underwriting fees, legal, accounting and other fees associated with the offering and paid by the Company of $3,257,000. The Company did not receive any proceeds from the shares sold by the selling stockholders. Selling stockholders paid a portion of the expenses related to their shares sold.

          The following discussion provides information which management believes is relevant to an assessment and an understanding of the Company’s operations and financial condition. This discussion should be read in conjunction with the attached unaudited condensed consolidated financial statements and accompanying notes as well as our annual report on Form 10-K for the fiscal year ended September 30, 2005.

      ��   Statements in this filing which are not historical facts are forward-looking statements under the provision of the Private Securities Litigation Reform Act of 1955. Such forward-looking statements include, without limitation, statements with respect to total estimated remaining contract values and the Company’s expectations regarding the U.S. government’s procurement activities. Forward-looking statements are not guarantees of future performance and are based upon numerous assumptions about future conditions that could prove not to be accurate. Forward looking statements are subject to numerous risks and uncertainties, and our actual results could differ materially as a result of such risks and other factors. In addition to those risks specifically mentioned in this report and in the other reports filed by the Company with the Securities and Exchange Commission (including our Form 10-K for the fiscal year ended September 30, 2005), such risks and uncertainties include, but are not limited to: the availability of U.S. and international government funding for our products and services; changes in the U.S. federal government procurement laws, regulations, policies and budgets (including changes to respond to budgetary constraints and cost-cutting initiatives); the number and type of contracts and task orders awarded to us; the exercise by the U.S. government of options to extend our contracts; our ability to retain contracts during any rebidding process; the timing of Congressional funding on our contracts; any government delay or termination of our contracts and programs; difficulties in developing and producing operationally advanced technology systems; the timing and customer acceptance of contract deliverables; our ability to attract and retain qualified personnel, including technical personnel and personnel with required security clearances; charges from any future impairment reviews; the future impact of any acquisitions or divestitures we may make; the competitive environment for defense and intelligence information technology products and services; general economic, business and political conditions domestically and internationally; and other factors affecting our business that are beyond our control. All of the forward-looking statements should be considered in light of these factors. You should not put undue reliance on any forward-looking statements. We undertake no obligation to update these forward-looking statements to reflect new information, future events or otherwise, except as provided by law.

          We are a leading systems engineering and development company providing full-service C4ISR (command, control, communications, computers, intelligence, surveillance and reconnaissance) systems to a wide range of defense and intelligence customers. Our systems provide communications intelligence, electromagnetic intelligence, electronic warfare and information operations capabilities that enable our defense and intelligence customers to detect, evaluate and respond to potential threats. These systems are deployed on a range of military and strategic platforms including surface ships, submarines, unmanned underwater vehicles (UUV), aircraft, unmanned aerial vehicles (UAV), land mobile vehicles, fixed site installations and re-locatable land sites.

          Our revenues are primarily generated from the design, development, installation and support of complex sensor systems under contracts primarily with the U.S. Government and major domestic prime contractors, as well as with foreign governments, agencies and defense contractors.

          Our government contracts can be divided into three major types: cost reimbursable, contracts, fixed-price, and time and materials. Cost reimbursable contracts are primarily used for system design and development activities involving considerable risks to the contractor, including risks related to cost estimates on complex systems, performance risks associated with real time signal processing, embedded software, high performance hardware, and requirements that are not fully understood by the customer or us, the development of technology that has never been used, and interfaces with other systems that are in development or are obsolete without adequate documentation.

          Fixed-price contracts are typically used for the production of systems. Development activities similar to activities performed under previous contacts are also usually covered by fixed-price contracts, due to the low risk involved. In these contracts, cost risks are borne entirely by the contractor. Some fixed-price contracts include an award fee or an incentive fee as well as the negotiated profit. Most foreign customers, and some U.S. customers, use fixed-price contracts for design and development work even when the work is considered high risk. Time and material contracts are based on hours worked, multiplied by approved labor rates, plus other costs incurred and allocated.

          The following table represents our revenue concentration by contract type for the fiscal quarters ended January 1, 2006 and January 2, 2005:periods indicated:

          From time to time, we will exclude from backlog portions of contract values of very long or complex contracts where we judge revenue could be jeopardized by a change in U.S. government policy. Because of possible future changes in delivery schedules and cancellations of orders, backlog at any particular date is not necessarily representative of actual sales to be expected for any succeeding period, and actual sales for the year may not meet or exceed the backlog represented.

          As of January 1,April 2, 2006, there was $5,957,000$6,280,000 of total unrecognized compensation cost related to nonvested share-based compensation arrangements. This cost is expected to be fully amortized in five years, with half of the total amortization cost being recognized within the next 24 months.

          Our discussion and analysis of our financial condition and results of operations are based upon our financial statements. These financial statements are prepared in accordance with accounting principles generally accepted in the United States, which require management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Actual results could differ significantly from those estimates. We believe that the estimates, assumptions, and judgments involved in the accounting practices described below have the greatest potential impact on our financial statements and, therefore, consider these to be critical accounting practices.

          If we anticipate that actual contract activities will be different than planned levels, there are alternatives we can utilize to absorb the variance: we can adjust planned indirect spending during the year, modify our billing rates to our customers, or record adjustments to expense based on estimates of future contract activities.

          If our rate variance is unfavorable, the modification of our indirect rates will likely increase revenue and operating expenses. Profit percentages on fixed-price contracts will generally decline as a result of an increase to indirect costs unless compensating savings can be achieved in the direct costs to complete the projects. Profit percentages on cost reimbursement contracts will generally decline as a percentage of total costs as a result of an increase in indirect costs even if the cost increase is funded by the customer. If our rate variance is favorable, the modification of our indirect rates will decrease revenue and operating expenses. In this event, profit percentages on fixed-price contracts will generally increase. Profit percentages on cost-reimbursable contracts will generally be unaffected as a result of any reduction to indirect costs, due to the fact that programs will typically expend all of the funds available. Any impact on operating income, however, will depend on a number of other factors, including mix of contract types, contract terms and anticipated performance on specific contracts.

The following table sets forth certain items, including consolidated contract revenues, cost of revenues, general and administrative expenses, interest income taxand interest expense, provision for income taxes and net income, and the changes in these items for the fiscal quarters ended January 1,April 2, 2006 and January 2,April 3, 2005:

          Cost of revenues increased approximately 9% for the six months ended April 2, 2006 as compared to the six months ended April 3, 2005. The increase was comprised primarily of increasesincrease in direct labor, materialssubcontracts and subcontractother direct costs of $1,510,000, $1,839,000$3,858,000, $3,736,000 and $2,514,000, respectively, related to increased production activities during the quarter. Under fringe benefits allocated to$3,141,000, respectively. These increases were offset by a decrease in material costs of revenue, compensated$7,867,000 due to our nearing completion of two significant production programs. Compensated leave increased $594,000,$1,093,000, 401k contributions increased $206,000 and$445,000, group insurance increased by $116,000. Under facilities allocated to costs of revenue,$395,000 and other fringe benefits increased $807,000 and rent increased by $125,000.$239,000. Business development costs increased by $267,000 over$458,000 and overhead travel increased $169,000 when compared to the quartersix months ended January 2,April 3, 2005. The increasesincrease in fringe benefits and facilities and business developmentcosts are related to an increase in employee population, andwhile the increase in business growth.development costs is consistent with our emphasis on penetrating new markets. Cost of revenues as a percentage of revenue decreased to 78% for the quartersix month period ended January 1,April 2, 2006 from 80%79% for the quartersix months ended January 2,April 3, 2005.

          General and administrative expenses increased approximately 79%38% for the fiscal quartersix months ended January 1,April 2, 2006, as compared to the fiscal quartersix months ended January 2,April 3, 2005. The increase was due primarily to an increase in labor of $357,000, accounting services of $326,000 and ana significant increase in bid and proposal costs of $1,824,000, related to$1,961,000, resulting from our pursuit of a number of competitively solicited procurements, for the quarter ended January 1, 2006. Themajor competitive program and an increase in accounting fees was primarily thesalaries expense of $703,000 as a result of Sarbanes-Oxley Section 404 compliance work performed during the 2005 fiscal year-end audit. The increase in labor is due to an increases in personnel and overall salary expense over the prior year.increased staff.

          Interest income decreasedincreased approximately $13,000$171,000 for the fiscal quartersix months ended January 1,April 2, 2006, as compared to the fiscal quartersix months ended January 2,April 3, 2005. This decreaseincrease was a result of lowersignificantly higher average cash balances.balances due to proceeds from our secondary stock offering in December 2005, improved accounts receivable collections, and higher short-term interest rates during the six months ended April 2, 2006 compared to the six months ended April 3, 2005. Interest expense was $127,000increased by $152,000 for the fiscal quartersix months ended January 1,April 2, 2006 compared to the six months ended April 3, 2005 due to borrowingborrowings on the line of credit. Duringcredit during the quarter ended January 2, 2005, there were no borrowings under the line.first quarter.

          Our effective income tax rate increased to 39.4%38.6% for the fiscal quartersix months ended January 1,April 2, 2006, compared to an effective rate of 38.3% for the fiscal quartersix months ended January 2,April 3, 2005. This increase was primarily due to the stock compensation expense related to incentive stock options granted during this period which areis not tax deductible in the period the expense is recorded.

          As a result of the above, netNet income increased approximately $683,000,$261,000, or 14%3%, for the fiscal quartersix months ended January 1,April 2, 2006 compared to the fiscal quartersix months ended JanuaryApril 3, 2005. This increase in net income reflects the shift in fixed price contract work from 79% of revenues during the six months ended April 3, 2005 to 67% of revenues during the six months ended April 2, 2005.2006.

          Cash

          At January 1,April 2, 2006, we had cash of $30,226,000$62,238,000 compared to cash of $4,064,000 on September 30, 2005. This increase in cash of $26,162,000$58,174,000 was primarily the result of the net proceeds from our secondary stock offering of $46,768,000, and a decrease in billed and unbilled receivables of $26,851,000 offset by the net repayment of the line of credit of $13,480,000 and an increase in billed and unbilled receivables of $9,764,000.$11,000,000.

          Cash Flows

          Net cash used inprovided by operating activities was $11,061,000 in$21,240,000 for the fiscal quartersix months ending January 1,April 2, 2006, compared to net cash provided by operating activities of $12,018,000 in fiscal quarter$1,623,000 for the six months ending January 2,April 3, 2005. The decreaseincrease in net cash from operating activities for fiscal quarterthe six months ending January 1,April 2, 2006 period compared to the fiscal quartersix months ending January 2,April 3, 2005 was primarily caused by a decrease in deferred revenuesbilled and unbilled accounts receivable of $17,161,000 and$31,929,000, a decrease in income taxes receivable of $6,256,000, partially offset by a decrease in accounts payable and accrued expenses of $11,291,000$16,999,000 and a decrease in the sumdeferred revenue of $1,676,000. The decrease in billed and unbilled receivables resulted from improved collection processes, and the achievement of $3,017,000, partially offset by an increase in income taxes payable of $5,915,000.contractual milestones. The decrease in deferred revenue resulted from our recognition of revenue during the six months ended April 2, 2006, related to milestone payments received during the fourth fiscal quarter of 2004 and the first fiscal quarter of 2005. See “ —– Overview —– Deferred Revenue” above.

Net cash provided byused in investing activities was $378,000$2,656,000 for the fiscal quartersix months ended January 1,April 2, 2006, compared to net cash used in investing activities of $1,613,000$2,292,000 for the fiscal quartersix months ended January 2,April 3, 2005. The increase is due primarily to the acquisition of certain assets of Pro Design Solutions, LLC. The increase in cash of $1,107,000 acquiredused in investing activities was partially offset by a decrease in the Radix acquisition. Investment inacquisition of property, equipment and software decreased by $884,000 as compared to fiscal quarter ended January 2, 2005. During that quarter, we completed work on our testing and engineering facility in Lemont Furnace, PA.software.

          Net cash provided by financing activities was $36,845,000$39,590,000 for the fiscal quartersix months ended January 1,April 2, 2006 compared to $2,292,000$3,158,000 for the fiscal quartersix months ended January 2,April 3, 2005. The increase in net cash provided by financing activities was primarily due to the net proceeds from our secondary stock offering of $46,768,000, partially offset by the repayment of the line of credit and a decrease of proceeds from exercise of stock options.

          As of January 1,April 2, 2006, our contractual cash obligations were as follows:

          All unrestricted, highly liquid investments purchased with a remaining maturity of three months or less are considered to be cash equivalents. We maintain cash and cash equivalents with various financial institutions in excess of the amount insured by the Federal Deposit Insurance Corporation. We believe that any credit risk related to these cash and cash equivalents is minimal.

          Our line of credit financing provides available borrowing to us at a variable interest rate tied to LIBOR or the bank’s primebasic interest rate. There were no outstanding borrowings under this line of credit at January 1, 2006..April 2, 2006. Accordingly, we do not believe that any movement in interest rates would have a material impact on future earnings or cash flows.

          We have contracts to provide services to certain foreign countries approved by the U.S. government. Our foreign sales contracts require payment in U.S. dollars, and therefore are not affected by foreign currency fluctuations. We occasionally issue orders or subcontracts to foreign companies in local currency. The current obligations to foreign companies are of an immaterial amount and we believe the associated currency risk is also immaterial.

          The information called for by this item is provided under Item 2 — “Management’s Discussion and Analysis of Financial Condition and Results of Operations.”

          None.

          Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.