Exhibit 5.1

                            (Lee and Li Letterhead)

                                                          May 7, 2007
                                                          Ref. No. 07-0023
                                                                   T12073/M122-6


Taiwan Semiconductor Manufacturing Company Limited
No. 8, Li-Hsin Road 6
Hsinchu Science Park
Hsinchu, Taiwan
Republic of China


Ladies and Gentlemen:

We act as special Republic of China (the "ROC") counsel for Taiwan Semiconductor
Manufacturing Company Limited (the "Company"), a company limited by shares
organized under the laws of the ROC, in connection with the registration under
the United States Securities Act of 1933, as amended (the "Act"), and the
contemplated issuance of American Depositary Shares (the "ADSs"), each ADS
representing 5 common shares, par value NT$10 per share (the "Common Shares"),
of the Company. The Common Shares are being registered pursuant to a
Registration Statement on Form F-3 under the Act (the "Registration Statement").

We have examined originals or copies, certified or otherwise identified to our
satisfaction, of such documents and records of the Company as we have deemed
necessary as a basis for the opinions hereinafter expressed. In such
examination, we have assumed the genuineness of all signatures, the authenticity
of all documents submitted to us as originals, the accuracy and completeness of
all documents submitted to us as copies and the authenticity of the originals of
such latter documents. As to matters of fact material to this opinion, we have
made due inquiries with and relied on the statements of officers and other
representatives of the Company, public officials or others.

Based upon the foregoing, we are of the opinion that:

1.   The Company has been duly incorporated and is validly existing as a company
     limited by shares under the laws of the ROC.

2.   The Common Shares underlying the ADSs have been duly authorized, issued,
     fully-paid and non-assessable.




3.   Subject to the conditions and qualifications described in the Registration
     Statement and the Company's annual report on Form 20-F for the year ended
     December 31, 2006 (the "Form 20-F"), the section of Form 20-F which is
     incorporated by reference in the Registration Statement entitled "Item 10.
     Additional Information -- Taxation -- R.O.C. Taxation", insofar as it
     relates to the ROC tax consequences currently applicable to the non-ROC
     holders of ADSs described therein, accurately reflects the material ROC tax
     consequences of owning ADSs.

We hereby consent to the use of this opinion in, and the filing hereof as an
Exhibit to, the Registration Statement, and to the reference to our name under
the headings "Enforceability of Civil Liabilities" and "Validity of Securities"
in the prospectus included in the Registration Statement. In giving such
consent, we do not thereby admit that we come within the category of person
whose consent is required under Section 7 of the Act or the regulations
promulgated thereunder.



Very truly yours,

LEE AND LI




/s/ Alex Jui-Lin Liu                        /s/ Chi-Chang Yu
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Alex Jui-Lin Liu                            Chi-Chang Yu