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                                                                     EXHIBIT 5.1

                                November 12, 2003

Amkor Technology, Inc.
Goshen Corporate Park
1345 Enterprise Drive
West Chester, PA 19380

         REGISTRATION STATEMENT ON FORM S-3; 8,050,000 SHARES OF COMMON STOCK

Dear Ladies and Gentlemen:

         In connection with the registration by Amkor Technology, Inc., a
Delaware corporation (the "Company"), of 7,000,000 shares of common stock of the
Company, par value $0.001 per share (and up to 1,050,000 additional shares
subject to an over-allotment option) (the "Shares"), pursuant to the Prospectus
Supplement filed on or about November 6, 2003 (the "Prospectus Supplement"), to
that certain Registration Statement on Form S-3 under the Securities Act of
1933, as amended (the "Act"), filed with the Securities and Exchange Commission
(the "Commission") on January 10, 2002 (File No. 333-76532), including Amendment
Nos. 1 and 2 thereto, and declared effective by the Commission (the
"Registration Statement"), you have requested our opinion with respect to the
matters set forth below. In our capacity as your special counsel in connection
with such registration, we are familiar with the proceedings taken and proposed
to be taken by the Company in connection with the authorization, issuance and
sale of the Shares, and for the purposes of this opinion, have assumed such
proceedings will be timely completed in the manner presently proposed. In
addition, we have made such legal and factual examinations and inquiries,
including an examination of originals or copies certified or otherwise
identified to our satisfaction of such documents, corporate records and
instruments, as we have deemed necessary or appropriate for purposes of this
opinion.

         In our examination, we have assumed the genuineness of all signatures,
the authenticity of all documents submitted to us as originals, the conformity
to authentic original documents of all documents submitted to us as copies and
the truth, accuracy and completeness of the information, representations and
warranties contained in the records, documents, instruments and certificates we
have reviewed.

         We are opining herein as to the effect on the subject transaction only
of the General Corporation Law of the State of Delaware, including statutory and
reported decisional law thereunder, and we express no opinion with respect to
the applicability thereto, or the effect

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Amkor Technology, Inc.
November 12, 2003
Page 2 of 2

thereon, of the laws of any other jurisdiction or, in the case of Delaware, any
other laws, or as to any matters of municipal law or the laws of any local
agencies within any state.

         Subject to the foregoing, we are of the opinion that the Shares, when
issued in the manner described in the Prospectus Supplement and the Registration
Statement, will be duly authorized, validly issued, fully paid and
non-assessable.

         We consent to the use of this opinion as an exhibit to the Registration
Statement, and further consent to the use of our name wherever appearing in the
Prospectus Supplement. In giving such consent, we do not believe that we are
"experts" within the meaning of such term as used in the Securities Act of 1933,
as amended, or the rules and regulations promulgated thereunder with respect to
any part of the Registration Statement, including this opinion as an exhibit or
otherwise.

                                            Very truly yours,

                                            WILSON SONSINI GOODRICH & ROSATI
                                            Professional Corporation

                                            /S/ WILSON SONSINI GOODRICH & ROSATI

