UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549


                                    FORM 10-K

[X]      Annual  report  pursuant  to  Section  13 or  15(d)  of the Securities
         Exchange Act of 1934 for the fiscal year ended December 31, 2004

[ ]      Transition report pursuant to Section 13 or 15(d) of the
         Securities Exchange Act of 1934 for the transition period from   to


                  Commission File Number  333-100818-47

                         GS MORTGAGE SECURITIES CORP.
            (as Depositor under the Pooling and Servicing Agreement,
             dated as of July 1, 2004, providing for the issuance of
              Mortgage Pass-Through Certificates, Series 2004-SD1)
             (Exact name of registrant as specified in its charter)

       Delaware                                       13-6357101
 (State or other jurisdiction of               (IRS Employer Identification No.)
     incorporation)

85 Broad Street
New York, NY                                                    10004
(Address of principal executive offices)                (Zip Code)

Registrant's telephone number, including area code :  (212) 902-1000


Securities registered pursuant to Section 12(b) of the Act:  None

Securities registered pursuant to Section 12(g) of the Act:  None

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 (or for such  shorter  period that the  registrant  was
required  to file  such  reports),  and  (2) has  been  subject  to such  filing
requirements for the past 90 days. Yes [X] No [ ]

Indicate by check mark if disclosure of delinquent  filers  pursuant to Item 405
of Regulation  S-K (229.405 of this chapter) is not contained  herein,  and will
not be contained,  to the best of registrant's knowledge, in definitive proxy or
information  statements  incorporated by reference in Part III of this Form 10-K
or any amendment to this Form 10-K. [X]

Indicate by check mark whether the registrant is an accelerated filer (as
defined in Exchange Act Rule 12b-2). Yes [ ]  No [X]

Indicate the number of shares outstanding of each of the registrant's
classes of common stock, as of the latest practicable date.

Not Applicable.

                    Documents incorporated by reference: None


<PAGE>

PART I

Item 1.  Business.

         Not Applicable.

Item 2.  Properties.

         Not Applicable.

Item 3.  Legal Proceedings.

     The Registrant knows of no material pending legal proceedings involving the
trust created under the Master Servicing and Trust Agreement,  the trustee,  any
servicer  or the  Registrant  with  respect  to the  trust  other  than  routine
litigation incidental to the duties of the respective parties.

Item 4.  Submission of Matters to a Vote of Security Holders

         None.

PART II

Item 5.  Market for Registrant's Common Equity and Related Stockholder Matters

     Currently,  there is no established  secondary  market for the Certificates
known to the Registrant.  As of December 31, 2004, the number of holders of each
class of offered certificates was 20 based on records provided by DTC.

Item 6.  Selected Financial Data.

         Not Applicable.

Item 7.  Management's Discussion and Analysis of Financial condition and
         Results of Operation.

         Not Applicable.

Item 7A. Quantitative and Qualitative Disclosures about Market Risk.

         Not Applicable.

Item 8.  Financial Statements and Supplementary Data.

         Not Applicable.

Item 9.  Changes in and Disagreements with Accountants on Accounting and
         Financial Disclosure.

         None.

Item 9A. Controls and Procedures.

         Not Applicable.

Item 9B. Other Information

         None.

                                      -2-

<PAGE>

PART III

Item 10. Directors and Executive Officers of the Registrant.

         Not Applicable.

Item 11. Executive Compensation.

         Not Applicable.

Item 12. Security  Ownership of Certain  Beneficial  Owners and Management
         and Related Stockholder Matters.

         Not Applicable.

Item 13. Certain Relationships and Related Transactions.

         No reportable transactions have occurred.

Item 14. Principal Accounting Fees and Services.

         Not applicable.

PART IV


Item 15. Exhibits, Financial Statement Schedules.

(a) The following documents are filed as part of this report:

    (1) Financial Statements:

        Not Applicable.

    (2)  Financial Statement Schedules:

         Not Applicable.

    (3)  Exhibits:

    Rule 13a-14(a)/15d-14(a) Certification, filed as Exhibit 31.1 hereto

    Annual Independent  Accountants' Report with Management Assertion,
    filed as Exhibit 99.1 hereto.

    Servicer's Annual Statement as to Compliance, filed as Exhibit 99.2 hereto.

(b) The exhibits required to be filed by Registrant pursuant to Item 601 of
    Regulation S-K are listed in Item (15)(a)(3) above.

(c) Not applicable.


                                      -3-
<PAGE>

GSAMP Trust 2004-SD1
Mortgage Pass-Through Certificates, Series 2004-SD1
-----------------------------------------------------------------------

SIGNATURE

Pursuant to the  requirements of Section 13 or 15(d) 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.



                              By:   /s/ Michelle Gill
                                   --------------------------------------
                            Name:  Michelle Gill
                           Title:  Vice President
                            Date:  March 30, 2005



                                      -4-
<PAGE>

SUPPLEMENTAL  INFORMATION TO BE FURNISHED WITH REPORTS FILED PURSUANT TO SECTION
15(D) OF THE ACT BY REGISTRANTS WHICH HAVE NOT REGISTERED SECURITIES PURSUANT TO
SECTION 12 OF THE ACT.

The  registrant  has not sent an annual report or proxy material to its security
holders.  The registrant  will not be sending an annual report or proxy material
to its security holders subsequent to the filing of this form.

                                      -5-
<PAGE>


                                 EXHIBIT INDEX

Exhibit     Description

31.1    Rule 13a-14(a)/15d-14(a) Certification

99.1    Annual Independent Accountants' Servicing Report
        with Management Assertion

        a) Chase Manhattan Mortgage Company, as Master Servicer
        a) Ocwen Federal Bank FSB, as Servicer

99.2    Annual Servicer's Statement as to Compliance

        a) Chase Manhattan Mortgage Company, as Master Servicer
        a) Ocwen Federal Bank FSB, as Servicer


                                      -6-
<PAGE>

                                  EXHIBIT 31.1
                 Annual Rule 13a-14(a)/15d-14(a) Certification

                            DEPOSITOR CERTIFICATION

     Re: GSAMP Trust 2004-SD1 (the "Trust") Mortgage Pass-Through  Certificates,
Series 2004-SD1,  issued pursuant to the Pooling and Servicing Agreement,  dated
as of July 1, 2004 (the  "Pooling and Servicing  Agreement"),  among GS Mortgage
Securities  Corp.,  as depositor (the  "Depositor"),  Ocwen Federal Bank FSB, as
servicer  ("Ocwen"),  Chase Manhattan Mortgage Company,  as Master Servicer (the
"Master  Servicer"),  Wachovia  Bank,  National  Association,  as  Trustee  (the
"Trustee") and JPMorgan Chase Bank, as Securities Administrator (the "Securities
Administrator")

I, Michelle Gill , certify that:

     1. I have reviewed this annual report on Form 10-K ("Annual  Report"),  and
all reports on Form 8-K containing  distribution reports (collectively with this
Annual Report,  the "Reports")  filed in respect of periods included in the year
covered by this Annual Report, of the Trust;

     2. Based on my knowledge, the information in the Reports, taken as a whole,
does not  contain  any untrue  statement  of a material  fact or omit to state a
material  fact  necessary  to  make  the  statements   made,  in  light  of  the
circumstances  under which such  statements  were made, not misleading as of the
last day of the period covered by this Annual Report;

     3.  Based  on my  knowledge,  the  distribution  or  servicing  information
required  to be  provided  to the  Trustee  by the  Servicers  under  the  Trust
Agreement and Servicing Agreements,  for inclusion in the Reports is included in
the Reports;

     4. Based on my knowledge and upon the annual compliance  statement included
in this Annual  Report and required to be delivered to the Trustee in accordance
with the terms of the  Servicing  Agreements,  and  except as  disclosed  in the
Reports,  the Servicers have  fulfilled  their  obligations  under the Servicing
Agreements; and

     5. The  Reports  disclose  all  significant  deficiencies  relating  to the
Servicer's compliance with the minimum servicing standards based upon the report
provided by an  independent  public  accountant,  after  conducting  a review in
compliance with the Uniform Single  Attestation  Program for Mortgage Bankers or
similar  procedure,  as set forth in the Trust  Agreement,  that is  included in
the Reports.

     In giving the certifications above, I have reasonably relied on information
provided  to me by the  following  unaffiliated  parties:  the  Trustee  and the
Servicer.

     Date:  March 30, 2005
           --------------------------------

       By:   /s/ Michelle Gill
            --------------------------------------
     Name:  Michelle Gill
     Title: Vice President

                                      -7-
<PAGE>



EXHIBIT 99.1 - Annual Independent Accountants' Report with Management Assertion


<PAGE>


Chase Manhattan Mortgage Corporation
------------------------------------------------------------



PricewaterhouseCoopers, LLP
PricewaterhouseCoopers Center
300 Madison Avenue
New York, NY  10017
Telephone:  (646)  471-3000
Facsimile:  (813)  286-6000


                       Report of Independent Auditors


To the Board of Directors of
Chase Manhattan Mortgage Corporation:


We  have  examined   management's   assertion  about  Chase  Manhattan  Mortgage
Corporation's (the "Company") compliance with the minimum servicing standards as
set forth in the  Mortgage  Bankers  Association  of  America's  Uniform  Single
Attestation  Program for Mortgage  Bankers ("USAP") as of and for the year ended
December 31, 2004. The Company has  interpreted  USAP and  determined  that USAP
minimum  servicing  standards I.1, I.2, I.3, III.1,  III.5,  IV.1, and VII.1 are
applicable to master servicers and are included in the  accompanying  management
assertion  (see  Exhibit  I).   Management  is  responsible  for  the  Company's
compliance with these minimum  servicing  standards.  Our  responsibility  is to
express an opinion on  management's  assertion,  as it relates to the  Company's
compliance with the  aforementioned  minimum servicing  standards,  based on our
examination.  The Company has interpreted  USAP and determined that USAP minimum
servicing  standards I.4, II.1, II.2, II.3, II.4, III.2,  III.3,  III.4,  III.6,
V.1, V.2, V.3, V.4 and VI.1 are not applicable to master servicers.  The Company
uses a subservicing organization to perform the servicing obligations subject to
servicing  standards I.4, II.1, II.2, II.3, II.4, III.2,  III.3,  III.4,  III.6,
V.1,  V.2,  V.3,  V.4,  and VI.1 of the USAP.  We did not examine the  Company's
compliance with the servicing standards referred to in the previous sentence and
accordingly, do not express an opinion thereon.

Our examination was made in accordance with attestation standards established by
the  American  Institute  of  Certified  Public  Accountants  and,  accordingly,
included  examining,  on a test basis,  evidence about the Company's  compliance
with the minimum  servicing  standards and performing such other such procedures
as we considered necessary in the circumstances. We believe that our examination
provides a reasonable basis for our opinion.  Our examination does not provide a
legal  determination  on the  Company's  compliance  with the minimum  servicing
standards.

In our  opinion,  management's  assertion  that the  Company  complied  with the
aforementioned  minimum  servicing  standards solely as they relate to standards
I.1,  I.2,  I.3,  III.1,  III.5,  IV.1,  and VII.1 as of and for the year  ended
December 31, 2004 is fairly stated, in all material respects.


By:  /s/ PricewaterhouseCoopers, LLC
------------------------------------
PricewaterhouseCoopers, LLC


March 23,  2005


                                                                   EXHIBIT I


             Management's Assertion Concerning Compliance with USAP
                          Minimum Servicing Standards


March 23, 2005

As of and for  the  year  ended  December  31,  2004,  Chase  Home  Finance  LLC
(successor by merger to Chase Manhattan  Mortgage  Corporation)  (the "Company")
has complied in all material respects with the minimum  servicing  standards set
forth  in  the  Mortgage  Bankers   Association  of  America's   Uniform  Single
Attestation  Program for Mortgage  Bankers  ("USAP") that we have determined are
applicable to master  servicers.  We have  interpreted  USAP and determined that
minimum servicing  standards I.1, I.2, I.3, III.1, III.5, IV.1, and VII.1 as set
forth in USAP are applicable to master servicers.  We have also interpreted that
USAP minimum  servicing  standards I.4, II.1, II.2, II.3,  II.4,  III.2,  III.3,
III.4,  III.6,  V.1,  V.2,  V.3,  V.4 and  VI.1  as set  forth  in USAP  are not
applicable  to master  servicers;  for these  minimum  servicing  standards  the
Company relies on the performance of its  subservicers.  This assertion  relates
specifically to the Company's Master Servicing Portfolio.

It is  the  Company's  policy  to  obtain  and  review  USAP  reports  from  the
independent  auditors of its  subservicers on an annual basis.  Not all of those
USAP reports for the year ended  December 31, 2004 are available as of March 23,
2005. As of March 23, 2005, the Company has obtained USAP reports for 32% of its
subservicers.  These  subservicers  serviced loans  comprising 90% of the unpaid
principal balance of the Company's Master Servicing Portfolio as of December 31,
2004.  Instances of  non-compliance  noted in the USAP reports received from the
subservicers as of March 23, 2005, have been included in Exhibit II hereto.

As of and for this same period, the Company had in effect fidelity bond and
errors and omissions  policy in the amounts of  $250,000,000  and  $25,000,000,
respectively.


By:  /s/ Diane Bentz
-----------------------------
Diane Bentz
Senior Vice President
Chase Home Finance LLC

By: /s/  Bonnie Collins
-----------------------------
Bonnie Collins
Senior Vice President
Chase Home Finance LLC




                                                                Exhibit II

                      Chase Manhattan Mortgage Corporation
                      Subservicers' USAP Report Exceptions


It is the policy of Chase  Manhattan  Mortgage  Corporation  (the  "Company") to
obtain Uniform Single Attestation  Program for Mortgage Bankers ("USAP") reports
from the independent  auditors of its  subservicers as of and for the year ended
December 31, 2004.  As of March 23, 2005,  the Company has obtained and reviewed
USAP reports for 32% of its  subservicers.  These  subservicers  serviced  loans
comprising 90% of the unpaid principal balance of the Company's Master Servicing
Portfolio as of December 31, 2004. The Company noted instances of  noncompliance
included in the USAP reports received as of March 23, 2005, which are summarized
below.



Servicer                                        Exception

Cendant Mortgage  Corporation     The Company did not comply with the
                                  requirement to prepare custodial bank account
                                  reconciliations within 45 calendar days after
                                  the cutoff date and the requirement to resolve
                                  reconciling items within 90 calendar days of
                                  their original identification as specified by
                                  their minimum servicing standards.


North Fork Bancorporation, Inc.   The mortgage interest rate changes on certain
                                  Home Equity Lines of Credit were not adjusted
                                  at the appropriate date in accordance with
                                  the mortgagor's loan documents. This resulted
                                  in the mortgagor being overcharged for the
                                  period from the interest rate change until
                                  the correct effective date, which was the
                                  first day of the following month.


GMAC Mortgage Corporation         There were bank accounts over the course of
                                  several months where the Company was not in
                                  full compliance with USAP requirements as it
                                  related to the preparation of custodial bank
                                  reconciliations within 45 calendar days of
                                  cutoff as well as the resolution of
                                  reconciling items within 90 calendar days of
                                  original identification. The Company
                                  remediated the issues related to the
                                  preparation of custodial bank accounts
                                  reconciliations within 45 calendar days as of
                                  December 31, 2004.




<PAGE>


PricewaterhouseCoopers LLP
222 Lakeview Avenue
Suite 360
West Palm Beach, FL 33401


INDEPENDENT CERTIFIED PUBLIC ACCOUNTANT'S REPORT

To the Board of Directors
Ocwen Federal Bank FSB

We have examined management's assertion, included in the accompanying Management
Assertion on Compliance with USAP, that, except for the noncompliance related to
reconciliations  described in the third paragraph and the noncompliance  related
to adjustable  rate mortgages  described in the fifth  paragraph,  Ocwen Federal
Bank FSB (the "Bank") complied with the minimum servicing  standards  identified
in the Mortgage  Bankers  Association  of  America's  ("MBA's")  Uniform  Single
Attestation  Program for Mortgage  Bankers ("USAP") as of and for the year ended
December 31, 2004.  Management is  responsible  for the Bank's  compliance  with
those minimum servicing  standards.  Our responsibility is to express an opinion
on management's assertion about the Bank's compliance based on our examination.

Our  examination  was  made in  accordance  with  standards  established  by the
American  Institute of Certified Public Accountants and,  accordingly,  included
examining,  on a test  basis,  evidence  about the  Bank's  compliance  with the
minimum servicing  standards and performing other such procedures as we consider
necessary  in the  circumstances.  We believe  that our  examination  provides a
reasonable  basis for our  opinion.  Our  examination  does not  provide a legal
determination on the Bank's compliance with the minimum servicing standards.

Our examination disclosed noncompliance with minimum servicing standards related
to account  reconciliations and adjustable rate mortgages applicable to the Bank
during the year ended December 31, 2004. Such  noncompliance is described in the
accompanying Management Assertion on Compliance with USAP.

In  our  opinion,  management's  assertion  that  the  Bank  complied  with  the
aforementioned   minimum  servicing  standards,   except  for  noncompliance  as
described in the accompanying  Management  Assertion on Compliance with USAP, as
of and for the year ended  December 31, 2004 is fairly  stated,  in all material
respects.


By:  /s/PricewaterhouseCoopers, LLC
------------------------------------
PricewaterhouseCoopers, LLC

March 29, 2005



<PAGE>


                  MANAGEMENT ASSERTION ON COMPLIANCE WITH USAP

March 11, 2005

As of and for the year ended  December 31, 2004,  except as  specifically  noted
below, Ocwen Federal Bank FSB (the "Bank") has complied in all material respects
with  the  minimum  servicing  standards  set  forth  in  the  Mortgage  Bankers
Association  of  America's  ("MBA's")  Uniform  Single  Attestation  Program for
Mortgage Bankers ("USAP").

Standard: Reconciliations shall be prepared on a monthly basis for all custodial
bank accounts and related bank clearing accounts. These reconciliations shall be
mathematically accurate, be prepared within forty five (45) calendar days of the
cutoff  date;  be reviewed  and  approved  by someone  other than the person who
prepared the  reconciliation;  and document  explanations for reconciling items.
These  reconciling  items shall be resolved  within ninety (90) calendar days of
their original identification.

Certain  reconciling  items which arose during the year ended  December 31, 2004
were not cleared within 90 days of their original identification. Management has
developed and  implemented  an action plan and continues to resolve  outstanding
reconciling  items.  All  significant  reconciling  items have been isolated and
reviewed by the Bank, and the Bank believes these items will not have a material
impact on the status of any custodial accounts.

Standard:  Adjustments  on ARM  loans  shall be  computed  based on the  related
mortgage note and any ARM rider.


Certain ARM loans serviced by the Bank have odd due dates (i.e., due dates other
than the first day of the month).  The mortgage  notes or ARM riders for some of
the odd due date loans establish a look-back date for the applicable  index at a
certain number of days prior to each Change Date, for example,  45 days prior to
the effective  Change Date.  The Bank  determines  the  look-back  date by using
30-day month when  subtracting the actual number of look-back days stated in the
Mortgage Note or ARM rider from the effective Change Date. Some months that have
more or less than 30 days may therefore  have a  miscalculated  look-back  date,
resulting in the index rate being used on an incorrect  date,  but  generally no
more  than a  two-business  day  difference.  This has  resulted  in some  minor
differences  in the calculated  monthly  payment  amount,  which could be either
higher or lower, depending on the movement in interest rates.

Management  has  implemented  a  corrective  action plan to review the  internal
procedures  for  processing  these  types  of ARM  adjustments,  which  includes
adjusting the borrower  accounts where  necessary.  The Bank believes that these
differences did not have a material impact on any mortgagor or investor.

As of and for this same  period,  the Bank had in effect a fidelity  bond in the
amount  of  $15,000,000  and an errors  and  omissions  policy in the  amount of
$5,000,000.



By: /s/ Ronald M. Faris
------------------------
Ronald M. Faris
President


By: /s/ Scott W. Andreson
-------------------------
Scott W. Andreson
Senior Vice President of Residential Assets


By: /s/ Brian J. LaForest
--------------------------
Brian J. LaForest
Director of Investor Reporting


By: /s/ Paul E. Neff
--------------------
Paul E. Neff
Director of Servicing Operations


<PAGE>

          EXHIBIT 99.2 - Annual Servicer's Statement as to Compliance


                           OFFICER'S CERTIFICATION


Reference is made to each pooling and servicing agreement listed on Exhibit
A hereto (each, an "Agreement") entered into by Chase Home Finance LLC, as
successor by merger to Chase Manhattan Mortgage Corporation and JPMorgan Chase
Bank, N.A., as successor by merger to Chase Manhattan Mortgage Corporation (the
"Master Servicer").

Pursuant to Article III of the Pooling and Servicing Agreement,  the undersigned
Officers certifies to the following:

1.   A review of the  activities  of the Master  Servicer  during the  preceding
     calendar year and of its performance  under the Master Servicing  Agreement
     has been made under such officer's supervision.

2.   To the best of such Officer's  knowledge,  based on such review, the Master
     Servicer has fulfilled all its obligations under this Agreement  throughout
     such year,  or, if there has been a default in the  fulfillment of any such
     obligation,  specifying  each such  default  known to such  officer and the
     nature and status thereof and the action being taking by Master Servicer to
     cure such default.




Certified By:   /s/  Diane Bentz                Date:  March 15, 2005
                ----------------------                 ---------------
                Diane Bentz
                Senior Vice President
                Chase Home Finance LLC, as successor by merger to Chase
                Manhattan Mortgage Corporation


                /s/  Michele Paul            Date:  March 15, 2005
                ----------------------                 ---------------
                Michele Paul
                Vice President
                JPMorgan Chase Bank, N.A., as successor by merger to Chase
                Manhattan Mortgage Corporation


                                EXHIBIT A

Transaction                     Pooling and Servicing Agreement dated as of
-----------                     -------------------------------------------

GSR 2004-2F                     January 1, 2004
GSR 2004-3F                     February 1, 2004
GSR 2004-4                      February 1, 2004
GSAMP 2004-SEA1                 March 1, 2004
GSR 2004-6F                     May 1, 2004
GSR 2004-SD1                    July 1, 2004
GSR 2004-8F                     July 1, 2004
GSR 2004-9                      July 1, 2004
GSR 2004-10F                    August 1, 2004
GSR 2004-11                     August 1, 2004
GSRPM 2004-1                    August 1, 2004
GSMPS 2004-4                    October 4, 2004
GSR 2004-13F                    October 1, 2004
GSR 2004-15F                    December 1, 2004


<PAGE>


                             Ocwen Federal Bank FSB
              Compliance Certification Year ended December 31, 2004
                                 GSAMP 2004-SD1


The  undersigned  Officer of Ocwen Federal Bank FSB, (the  "Serivcer")  confirms
that a review of the  activities  of the Servicer  during the calendar  year
ending on December 31, 2004 and of the  performance  of the  Servicer  under the
Pooling and Servicing Agreement dated July 1, 2004 for GSAMP 2004-SD1 (the
"Servicing  Agreement") has been made under his supervision.  Except as noted on
the Management Assertion on Compliance with USAP, to the best of the undersigned
Officer's knowledge, based on such review, the Servicer has fulfilled all of its
obligations as set forth in the Servicing Agreement.

By:  /s/ Scott W. Anderson                      Dated:  March 15, 2005
----------------------------------------
Scott W. Anderson, Senior Vice President




                             Ocwen Federal Bank FSB
           1675 Palm Beach Lakes Boulevard, West Palm Beach, FL 33401
             Mail to: P.O. Box 24737, West Palm Beach, FL 33416-4737