UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

PURSUANT TO SECTION 13 OR 15(d) OF THE

SECURITIES EXCHANGE ACT OF 1934

Date of Report (Date of earliest event reported)

June 30, 2005

STRUCTURED ASSET SECURITIES CORPORATION (as Depositor under the Trust Agreement dated as of June 1, 2005, providing for the issuance of Lehman XS Trust Mortgage Pass-Through Certificates, Series 2005-1)

Structured Asset Securities Corporation

(Exact Name of Registrant as Specified in its Charter)

Delaware

333-120575

74-2440850

(State or Other Jurisdiction

Of Incorporation)

(Commission

File Number)

(I.R.S. Employer

Identification No.)

745 Seventh Avenue, 7^th Floor

New York, NY

(Address of Principal Executive Offices)

10019

(Zip Code)

Registrant’s telephone number, including area code: (212) 526-7000

No Change

(Former Name or Former Address, if Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

[ ] Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

[ ] Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

[ ] Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

[ ] Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 8.01. Other Events

The Registrant registered issuances of Lehman XS Trust Mortgage Pass-Through Certificates Series 2005-1, on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, as amended (the “Act”), by a Registration Statement on Form S-3 (Registration File No. 333-120575) (the “Registration Statement”). Pursuant to the Registration Statement, the Registrant issued approximately $873,316,000 in aggregate principal amount of Class 1-A1, Class 1-A2, Class 1-A3, Class 1-A4, Class 1-AX, Class 2-A1, Class 2-A2, Class M1, Class M2, Class M3, Class M4, Class 3-A1, Class 3-A2A, Class 3-A2B, Class 3-A3A, Class 3-A3B, Class 3-A4, Class 3-AIO, Class 3-M1, Class 3-M2 and Class 3-M3 Lehman XS Trust Mortgage Pass-Through Certificates, Series 2005-1 on June 30, 2005. This Current Report on Form 8-K is being filed to satisfy an undertaking, contained in the definitive Prospectus dated June 27, 2005, as supplemented by the Prospectus Supplement dated June 29, 2005 (the “Prospectus Supplement”) and the supplement to the Prospectus Supplement dated July 8, 2005, to file a copy of the Trust Agreement (as defined below) and other operative agreements executed in connection with the issuance of the Certificates, a form of which was filed as an exhibit to the Registration Statement.

The Offered Certificates (as defined herein) and the Other Certificates (as defined herein) were issued pursuant to a Trust Agreement (the “Trust Agreement”), attached hereto as Exhibit 4.1, dated as of June 1, 2005, among Structured Asset Securities Corporation, as depositor, Citibank, N.A., as Trustee and Aurora Loan Services LLC, as master servicer. The “Offered Certificates” consist of the following classes: Class 1-A1, Class 1-A2, Class 1-A3, Class 1-A4, Class 1-AX, Class 2-A1, Class 2-A2, Class M1, Class M2, Class M3, Class M4, Class 3-A1, Class 3-A2A, Class 3-A2B, Class 3-A3A, Class 3-A3B, Class 3-A4, Class 3-AIO, Class 3-M1, Class 3-M2 and Class 3-M3. The Offered Certificates and the “Other Certificates” (consisting of the Class X, Class 3-X, Class P, Class 3-P, Class R and Class 3-R Certificates), evidence all of the beneficial ownership interest in a trust fund (the “Trust Fund”) the assets of which will primarily consist of two pools of conventional, first lien, adjustable rate, fully amortizing residential mortgage loans and a third pool of conventional, first lien, fixed rate, fully amortizing residential mortgage loans (the “Mortgage Loans”) with an aggregate outstanding principal balance of approximately $879,043,165 as of June 1, 2005, together with certain other assets. Capitalized terms used herein and not otherwise defined shall have the meanings assigned to them in the Trust Agreement.

Item 9.01. Financial Statements and Exhibits

(a)

Not applicable.

(b)

Not applicable.

(c)

Exhibits:

4.1

Trust Agreement dated as of June 1, 2005, among Structured Asset Securities Corporation, as Depositor, Citibank, N.A., as Trustee and Aurora Loan Services LLC, as Master Servicer.

99.1

Mortgage Loan Sale and Assignment Agreement dated as of June 1, 2005, between Lehman Brothers Holdings Inc., as Seller, and Structured Asset Securities Corporation, as Purchaser.

99.2

Servicing Agreement dated as of June 1, 2005, among Aurora Loan Services LLC, as Master Servicer and Servicer, and Lehman Brothers Holdings Inc., as Seller.

99.3

Group 1 Senior Interest Rate Cap Agreement, dated as of June 30, 2005 (including schedules and trade confirms and ISDA Master Agreement (by reference)), each between Lehman Brothers Special Financing Inc. and Lehman XS Trust, Series 2005-1

99.4

Class 3-A1 Interest Rate Cap Agreement, dated as of June 30, 2005 (including schedules and trade confirms and ISDA Master Agreement (by reference)), each between Lehman Brothers Special Financing Inc. and Lehman XS Trust, Series 2005-1

99.5

Class 3-A2A Interest Rate Cap Agreement, dated as of June 30, 2005 (including schedules and trade confirms and ISDA Master Agreement (by reference)), each between Lehman Brothers Special Financing Inc. and Lehman XS Trust, Series 2005-1.

SIGNATURES

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 hereunto duly authorized.

STRUCTURED ASSET SECURITIES

CORPORATION

By: /s/ Michael Hitzmann

Name: Michael Hitzmann

Title: Vice President

Dated: June 30, 2005

EXHIBIT INDEX

Exhibit No.

Description

4.1

Lehman XS Trust Series 2005-1 8-K