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                                                                   EXHIBIT 10.12

                                                               EXECUTION VERSION

                                    GUARANTEE

          GUARANTEE, dated as of July 19, 2001, made by New Century Financial
Corporation (the "Guarantor"), on behalf of New Century Mortgage Corporation
("NCMC") and NC Capital Corporation (the "NCCC" and, together with NCMC, the
"Sellers"), in favor of CDC Mortgage Capital Inc. ("CDC"), a party to the
Repurchase Agreement and the Custodial Agreement, each referred to below.

                                    RECITALS

          Pursuant to that certain Master Repurchase Agreement, dated as of July
19, 2001 (as amended, supplemented or otherwise modified from time to time, the
"Repurchase Agreement"), between CDC and the Sellers, the Sellers have agreed to
sell, from time to time, to CDC certain mortgage loans (the "Mortgage Loans") as
whole loans upon the terms and subject to the conditions set forth therein. The
Guarantor owns directly and indirectly all interests in the Sellers. Pursuant to
the terms of that certain Custodial Agreement, dated as of July 19, 2001 (the
"Custodial Agreement", and collectively with the Repurchase Agreement, the
"Agreements"), U.S. Bank National Association (the "Custodian") is required to
take possession of the Mortgages and the Mortgage Notes, along with certain
other documents specified in the Agreements, as the Custodian of CDC and any
future purchaser, on several delivery dates, in accordance with the terms and
conditions of the Custodial Agreement. It is a condition precedent to the
obligation of CDC to purchase the Mortgage Loans under the Repurchase Agreement
that the Guarantor shall have executed and delivered this Guarantee with respect
to any and all representations, warranties, covenants and other obligations
(collectively, the "Obligations") of the Sellers with respect to CDC under each
of the Repurchase Agreement and the Custodial Agreement.

          NOW, THEREFORE, in consideration of the premises and to induce CDC to
enter into the Repurchase Agreement and the Custodial Agreement, the Guarantor
hereby agrees, for the benefit of CDC, as follows:

     1.   Defined Terms.

               (a)  Unless otherwise defined herein, terms defined in the
Repurchase Agreement and used herein shall have the meanings given to them in
the Repurchase Agreement.

               (b)  The words "hereof," "herein" and "hereunder" and words of
similar import when used in this Guarantee shall refer to this Guarantee as a
whole and not to any particular provision of this Guarantee, and section and
paragraph references are to this Guarantee unless otherwise specified.

               (c)  The meanings given to terms defined herein shall be equally
applicable to both the singular and plural forms of such terms.

     2.   Guarantee.

     (a)  The Guarantor hereby, unconditionally and irrevocably, guarantees, for
the benefit of CDC and its successors, indorsees, transferees and assigns, the
prompt and complete payment

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and performance by the Sellers when such payment is due or performance required
in accordance with the Obligations.

     (b)  Anything herein to the contrary notwithstanding, the maximum liability
of the Guarantor hereunder shall in no event exceed the amount which can be
guaranteed by the Guarantor under applicable federal and state laws relating to
the insolvency of the debtors.

     (c)  The Guarantor further agrees to pay any and all expenses (including,
without limitation, all fees and disbursements of counsel) which may be paid or
incurred by CDC in enforcing, or obtaining advice of counsel in respect of, any
rights with respect to, or collecting, any or all of the Obligations and/or
enforcing any rights with respect to, or collecting against, the Guarantor under
this Guarantee. This Guarantee shall remain in full force and effect until the
Obligations are performed and/or paid in full and the Agreements are terminated,
notwithstanding that from time to time prior thereto the Sellers may be free
from any Obligations.

     (d)  No actions or payments made by the Sellers, the Guarantor, any other
guarantor or any other Person or received or collected by CDC from the Sellers,
the Guarantor, any other guarantor or any other Person by virtue of any action
or proceeding or any set-off or appropriation or application at any time or from
time to time in reduction of or in payment of the Obligations shall be deemed to
modify, reduce, release or otherwise affect the liability of the Guarantor
hereunder which shall, notwithstanding any such payment or payments other than
payments made by the Guarantor in respect of the Obligations or payments
received or collected from the Guarantor in respect of the Obligations, remain
liable for the Obligations hereunder until the Obligations are paid in full and
the Agreements are terminated.

     (e)  The Guarantor agrees that whenever, at any time, or from time to time,
it shall make any payment to CDC on account of its liability hereunder, it will
notify CDC in writing that such payment or performance is made under this
Guarantee for such purpose.

     3.   Right of Set-off. The Guarantor hereby irrevocably authorizes CDC at
any time and from time to time without notice to the Guarantor, any such notice
being expressly waived by the Guarantor, to set-off and appropriate and apply
any and all deposits (general or special, time or demand, provisional or final),
in any currency, and any other credits, indebtedness or claims, in any currency,
in each case whether direct or indirect, absolute or contingent, matured or
unmatured, at any time held or owing by CDC to or for the credit or the account
of the Guarantor, or any part thereof in such amounts as CDC may elect, against
and on account of the obligations and liabilities of the Guarantor to CDC
hereunder and claims of every nature and description of CDC against the
Guarantor, in any currency, whether arising hereunder, or otherwise, as CDC may
elect, whether or not CDC has made any demand for payment and although such
obligations, liabilities and claims may be contingent or unmatured. CDC shall
notify the Guarantor promptly of any such set-off and the application made by
CDC, provided that the failure to give such notice shall not affect the validity
of such set-off and application. The rights of CDC under this Section are in
addition to other rights and remedies (including, without limitation, other
rights of set-off) which CDC may have.

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     4.   No Subrogation. Notwithstanding any payment or payments made by the
Guarantor hereunder or any set off or application of funds of the Guarantor by
CDC, the Guarantor shall not be entitled to be subrogated to any of the rights
of CDC against the Sellers or any other guarantor or any collateral security or
guarantee or right of offset held by CDC for the payment of the Obligations, nor
shall the Guarantor seek or be entitled to seek any contribution or
reimbursement from the Sellers or any other guarantor in respect of any payments
made by the Guarantor hereunder, until all amounts owing to CDC are paid in full
and the Agreements are terminated. If any amount shall be paid to the Guarantor
on account of such subrogation rights at any time when all of the Obligations
shall not have been paid in full, such amount shall be held by the Guarantor in
trust for CDC segregated from other funds of the Guarantor, and shall, forthwith
upon receipt by the Guarantor, be turned over to CDC, in the exact form received
by the Guarantor (duly indorsed by the Guarantor to CDC, if required), to be
applied against the Obligations, whether matured or unmatured, in such order as
CDC may determine.

     5.   Amendments, etc. with respect to the Obligations; Waiver of Rights.
The Guarantor shall remain obligated hereunder notwithstanding that, without any
reservation of rights against the Guarantor and without notice to or further
assent by the Guarantor, any demand for repurchase or other performance or
payment under any of the Obligations made by CDC may be rescinded by such party
and any of the Obligations continued, and the Obligations, or the liability of
any other party upon or for any part thereof, or any collateral security or
guarantee therefor or right of offset with respect thereto, may, from time to
time, in whole or in part, be renewed, extended, amended, modified, accelerated,
compromised, waived, surrendered or released by CDC, and the Agreements and any
other documents executed and delivered in connection therewith may be amended,
modified, supplemented or terminated, in whole or in part, as CDC may deem
advisable from time to time, and any collateral security, guarantee or right of
offset at any time held by CDC for the payment of the Obligations may be sold,
exchanged, waived, surrendered or released. CDC shall have no obligation to
protect, secure, perfect or insure any lien at any time held by it as security
for the Obligations or for this Guarantee or any property subject thereto. When
making any demand hereunder against the Guarantor, CDC may, but shall be under
no obligation to, make a similar demand on the Sellers or any other guarantor,
and any failure by CDC to make any such demand or to collect any payments from
the Sellers or any such other guarantor or any release of the Sellers or such
other guarantor shall not relieve the Guarantor of its obligations or
liabilities hereunder, and shall not impair or affect the rights and remedies,
express or implied, or as a matter of law, of CDC against the Guarantor. For the
purposes hereof "demand" shall include the commencement and continuance of any
legal proceedings.

     6.   Guarantee Absolute and Unconditional. The Guarantor waives any and all
notice of the creation, renewal, extension or accrual of any of the Obligations
and notice of or proof of reliance by CDC upon this Guarantee or acceptance of
this Guarantee, and any creation, renewal extension or accrual of any of the
Obligations, shall conclusively be deemed to have been created, contracted or
incurred, or renewed, extended, amended or waived, in reliance upon this
Guarantee; and all dealings between the Sellers and the Guarantor, on the one
hand, and CDC and the Sellers, on the other hand, likewise shall be conclusively
presumed to have been had or consummated in reliance upon this Guarantee. The
Guarantor waives diligence, presentment, protest, demand for payment and notice
of default or nonpayment to or upon the Sellers or the Guarantor with respect to
the Obligations. The Guarantor understands and agrees that this

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Guarantee shall be construed as a continuing, absolute and unconditional
guarantee of payment and not of collection without regard to (a) the validity,
regularity or enforceability of the Repurchase Agreement, the Custodial
Agreement, or any other document, any of the Obligations or any other collateral
security therefor or guarantee or right of offset with respect thereto at any
time or from time to time held by CDC, (b) any defense, set-off or counterclaim
(other than a defense of payment or performance) which may at any time be
available to or be asserted by the Sellers against CDC, or (c) any other
circumstance whatsoever (with or without notice to or knowledge of the Sellers
or the Guarantor) which constitutes, or might be construed to constitute, an
equitable or legal discharge of the Sellers for the Obligations, or of the
Guarantor under this Guarantee, in bankruptcy or in any other instance. When
pursuing its rights and remedies hereunder against the Guarantor, CDC may, but
shall be under no obligation to, pursue such rights and remedies as it may have
against the Sellers or any other Person or against any collateral security or
guarantee for the Obligations or any right of offset with respect thereto and
any failure by CDC to pursue such other rights or remedies or to collect any
payments from the Sellers or any such other Person or to realize upon any such
collateral security or guarantee or to exercise any such right of offset, or any
release of the Sellers or any such other Person or any such collateral security,
guarantee or right of offset shall not relieve the Guarantor of any liability
hereunder, and shall not impair or affect the rights and remedies, whether
express, implied or available as a matter of law, of CDC against the Guarantor.
This Guarantee shall remain in full force and effect and be binding in
accordance with and to the extent of its terms upon the Guarantor and the
successors and assigns thereof, and shall inure to the benefit of CDC, and its
respective successors, indorsees, transferees and assigns, until all the
Obligations and the obligations of the Guarantor under this Guarantee shall have
been satisfied by complete performance and payment in full and the Agreements
shall be terminated, notwithstanding that from time to time during the term of
the Agreements the Guarantor may be free from any Obligations.

     7.   Reinstatement. This Guarantee shall continue to be effective, or be
reinstated, as the case may be, if at any time payment and/or performance, or
any part thereof, of any of the Obligations is rescinded or must otherwise be
restored or returned by CDC upon the insolvency, bankruptcy, dissolution,
liquidation or reorganization of the Sellers or the Guarantor, or upon or as a
result of the appointment of a receiver, intervenor or conservator of, or
trustee or similar officer for, the Sellers or the Guarantor or any substantial
part of their respective property, or otherwise, all as though such payments had
not been made.

     8.   Payments. The Guarantor hereby guarantees that payments hereunder will
be paid to CDC without set-off or counterclaim in U.S. Dollars at the office of
CDC as specified in Section 8 of the Repurchase Agreement.

     9.   Representations and Warranties. The Guarantor hereby represents and
warrants that:

     (a)  it is duly organized, validly existing and in good standing under the
laws of the state of California and has the corporate power and authority and
the legal right to own and operate its property, to lease the property it
operates as lessee and to conduct the business in which it is currently engaged;

                                      -4-

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     (b)  it has the corporate power and authority and the legal right to
execute and deliver, and to perform its obligations under, this Guarantee, and
has taken all necessary corporate action to authorize its execution, delivery
and performance of this Guarantee;

     (c)  this Guarantee has been duly executed and delivered on behalf of the
Guarantor, and constitutes a legal, valid and binding obligation of the
Guarantor enforceable in accordance with its terms, subject to the effects of
bankruptcy, insolvency, fraudulent conveyance, reorganization, moratorium and
other similar laws relating to or affecting creditors' rights generally, general
equitable principles (whether considered on a proceeding in equity or at law)
and an implied covenant of good faith and fair dealing;

     (d)  neither the execution and delivery of this Guarantee, nor the
fulfillment of or compliance with the terms and conditions of this Guarantee,
will conflict with or result in a breach of any of the terms, conditions or
provisions of the Guarantor's charter or by-laws or any legal restriction or any
agreement or instrument to which the Guarantor is now a party or by which it is
bound, or constitute a default or result in an acceleration under any of the
foregoing, or result in the violation of any law, rule, regulation, order,
judgment or decree to which the Guarantor or its property is subject;

     (e)  no consent or authorization of, filing with, notice to, or other act
by or in respect of, any governmental authority or any other Person (including,
without limitation, any stockholder or creditor of the Guarantor) is required in
connection with the execution, delivery, performance, validity or enforceability
of this Guarantee;

     (f)  there are no actions, suits, arbitrations, investigations (including,
without limitation, any of the foregoing which are pending or threatened) or
other legal or arbitrable proceedings affecting the Guarantor or any of its
subsidiaries or affecting any of its properties before any governmental
authority which (i) questions or challenges the validity or enforceability of
the Agreements or any action to be taken in connection with the transactions
contemplated thereby, (ii) makes a claim or claims in an aggregate amount
greater than $500,000, or (iii) individually or in the aggregate, if adversely
determined, could reasonably be likely to have a Material Adverse Effect (as
defined in the Repurchase Agreement).

     (g)  it has good record and marketable title in fee simple to, or a valid
leasehold interest in, all its real property, and good title to, or a valid
leasehold interest in, all its other property, and none of such property is
subject to any lien of any nature whatsoever except such as are disclosed in the
balance sheet referred to in Section 9(h) hereof;

     (h)  it has filed or caused to be filed all tax returns which, to its
knowledge, are required to be filed and has paid all taxes shown to be due and
payable on said returns or on any assessments made against it or any of its
property and all other taxes, fees or other charges imposed on it or any of its
property by any governmental authority (other than any amount or validity of
which is currently being contested in good faith by appropriate proceedings and
with respect to which reserves in conformity with GAAP have been provided on the
books of the Guarantor); no tax lien has been filed, and, to the knowledge of
the Guarantor, no claim is being asserted, with respect to any such tax, fee or
other charge; and

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     (i)  The consolidated balance sheet of the Guarantor as of December 31,
2000 and the related consolidated statements of income and retained earnings and
of cash flows for such fiscal year, reported on by KPMG LLC, copies of which
have heretofore been furnished to CDC, are complete and correct and present
fairly the financial condition of the Guarantor as at such date, and the results
of its operations and its cash flow for such fiscal year. The consolidated
balance sheet of the Guarantor for the quarterly fiscal period as of March 31,
2001 and its consolidated balance sheet as of May 31, 2001 and the related
consolidated statements of income and retained earnings and of cash flows for
such period, certified by a responsible officer, copies of which have heretofore
been furnished to CDC, are complete and correct and present fairly the financial
condition of the Guarantor as of such date, and the results of its operations
and its cash flows for such periods (subject to normal year-end audit
adjustments). All such financial statements, including the related schedules and
notes thereto, have been prepared in accordance with GAAP applied consistently
throughout the periods involved (except as approved by such accountants or
responsible officer, as the case may be, and as disclosed therein). At the date
of the most recent balance sheet referred to above, the Guarantor had no
material guarantee obligation, contingent liability or liability for taxes, or
any long-term lease or unusual forward or long-term commitment, including,
without limitation, any interest rate or foreign currency swap or exchange
transaction or other financial derivative, which is not reflected in the
foregoing statements or in the notes thereto. During the period from May 31,
2001, to and including the date hereof there has been no sale, transfer or other
disposition by the Guarantor of any material part of its business or property
and no purchase or other acquisition of any business or property (including any
capital stock of any other Person) material in relation to the financial
condition of the Guarantor at July 19, 2001.

     10.  Notices. All notices, requests and demands which are required or
permitted to be given under this Guarantee shall be in writing (or by telex, fax
or similar electronic transfer confirmed in writing) and shall be deemed to have
been duly given or made (1) when delivered by hand or (2) if given by mail, when
deposited in the mails by certified mail, return receipt requested, or (3) if by
telex, fax or similar electronic transfer, when sent and receipt has been
confirmed, addressed as follows:

     (a)  if to CDC or to the Sellers, at their respective addresses or
transmission numbers for notices provided in Section 17 of the Repurchase
Agreement; and

     (b)  if to the Guarantor, at its address or transmission number for notices
set forth under its signature below.

          CDC, the Sellers and the Guarantor may change its address and
transmission numbers for notices by notice in the manner provided in this
Section.

     11.  Severability. Any provision of this Guarantee which is prohibited or
unenforceable in any jurisdiction shall, as to such jurisdiction, be ineffective
to the extent of such prohibition or unenforceability without invalidating the
remaining provisions hereof, and any such prohibition or unenforceability in any
jurisdiction shall not invalidate or render unenforceable such provision in any
other jurisdiction.

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     12.  Integration. This Guarantee represents the agreement of the Guarantor
with respect to the subject matter hereof.

     13.  Amendments in Writing; No Waiver; Cumulative Remedies.

     (a)  None of the terms or provisions of this Guarantee may be waived,
amended, supplemented or otherwise modified except by a written instrument
executed by the Guarantor, the Sellers and CDC.

     (b)  CDC shall not by any act, delay, indulgence, omission or otherwise be
deemed to have waived any right or remedy hereunder or to have acquiesced in any
breach of any of the terms and conditions hereof. No failure to exercise, nor
any delay in exercising, on the part of CDC, any right, power or privilege
hereunder shall operate as a waiver thereof. No single or partial exercise of
any right, power or privilege hereunder shall preclude any other or further
exercise thereof or the exercise of any other right, power or privilege. A
waiver by CDC of any right or remedy hereunder on any one occasion shall not be
construed as a bar to any right or remedy which CDC would otherwise have on any
future occasion.

               The rights and remedies herein provided are cumulative, may be
exercised singly or concurrently and are not exclusive of any other rights or
remedies provided by law.

     14.  Section Headings. The section headings used in this Guarantee are for
convenience of reference only and are not to affect the construction hereof or
be taken into consideration in the interpretation hereof.

     15.  Successors and Assigns. This Guarantee shall be binding upon the
successors and assigns of the Guarantor and shall inure to the benefit of CDC
and its successors and assigns. This Guarantee may not be assigned by the
Guarantor without the prior written consent of CDC, which consent shall be at
CDC's sole discretion. This Guarantee may be assigned by CDC without the consent
of the Guarantor to any assignee of the Repurchase Agreement.

     16.  GOVERNING LAW. THIS GUARANTEE SHALL BE GOVERNED BY, AND CONSTRUED IN
ACCORDANCE WITH, THE LAW OF THE STATE OF NEW YORK WITHOUT REGARD TO CONFLICTS OF
LAW PRINCIPALS.

     17.  SUBMISSION TO JURISDICTION; WAIVERS. THE GUARANTOR HEREBY IRREVOCABLY
AND UNCONDITIONALLY:

     (a)  SUBMITS FOR ITSELF AND ITS PROPERTY IN ANY LEGAL ACTION OR PROCEEDING
RELATING TO THIS GUARANTEE AND THE AGREEMENTS, OR FOR RECOGNITION AND
ENFORCEMENT OF ANY JUDGMENT IN RESPECT THEREOF, TO THE EXCLUSIVE GENERAL
JURISDICTION OF THE COURTS OF THE STATE OF NEW YORK, THE FEDERAL COURTS OF THE
UNITED STATES OF AMERICA FOR THE SOUTHERN DISTRICT OF NEW YORK, AND APPELLATE
COURTS FROM ANY THEREOF;

     (b)  CONSENTS THAT ANY SUCH ACTION OR PROCEEDING MAY BE BROUGHT IN SUCH
COURTS AND, TO THE EXTENT PERMITTED BY LAW, WAIVES

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ANY OBJECTION THAT IT MAY NOW OR HEREAFTER HAVE TO THE VENUE OF ANY SUCH ACTION
OR PROCEEDING IN ANY SUCH COURT OR THAT SUCH ACTION OR PROCEEDING WAS BROUGHT IN
AN INCONVENIENT COURT AND AGREES NOT TO PLEAD OR CLAIM THE SAME;

     (c)  AGREES THAT SERVICE OF PROCESS IN ANY SUCH ACTION OR PROCEEDING MAY BE
EFFECTED BY MAILING A COPY THEREOF BY REGISTERED OR CERTIFIED MAIL (OR ANY
SUBSTANTIALLY SIMILAR FORM OF MAIL), POSTAGE PREPAID, TO ITS ADDRESS SET FORTH
UNDER ITS SIGNATURE BELOW OR AT SUCH OTHER ADDRESS OF WHICH CDC SHALL HAVE BEEN
NOTIFIED; AND

     (d)  AGREES THAT NOTHING HEREIN SHALL AFFECT THE RIGHT TO EFFECT SERVICE OF
PROCESS IN ANY OTHER MANNER PERMITTED BY LAW OR SHALL LIMIT THE RIGHT TO SUE IN
ANY OTHER JURISDICTION.

     (e)  CDC AND GUARANTOR HEREBY IRREVOCABLY WAIVE, TO THE FULLEST EXTENT
PERMITTED BY APPLICABLE LAW, ANY AND ALL RIGHT TO TRIAL BY JURY IN ANY LEGAL
PROCEEDING ARISING OUT OF OR RELATING TO THIS GUARANTEE, THE AGREEMENTS, OR THE
TRANSACTIONS CONTEMPLATED HEREBY OR THEREBY.

     (f)  WAIVES, TO THE MAXIMUM EXTENT NOT PROHIBITED BY LAW, ANY RIGHT IT MAY
HAVE TO CLAIM OR RECOVER IN ANY LEGAL ACTION OR PROCEEDING REFERRED TO IN THIS
SECTION ANY SPECIAL, EXEMPLARY, PUNITIVE OR CONSEQUENTIAL DAMAGES.

     18.  Acknowledgments. The Guarantor hereby acknowledges that:

     (a)  it has been advised by counsel in the negotiation, execution and
delivery of this Guarantee;

     (b)  CDC does not have any fiduciary relationship with or duty to the
Guarantor arising out of or in connection with this Guarantee, and the
relationship between the Guarantor, the Sellers and CDC; and

     (c)  no joint venture is created hereby or otherwise exists by virtue of
the transactions contemplated hereby among the Guarantor, the Sellers and CDC.

     19.  WAIVER OF JURY TRIAL. THE GUARANTOR HEREBY IRREVOCABLY AND
UNCONDITIONALLY WAIVES TRIAL BY JURY IN ANY LEGAL ACTION OR PROCEEDING RELATING
TO THIS GUARANTEE OR ANY OTHER DOCUMENT RELATING HERETO OR THE MORTGAGE LOANS
AND FOR ANY COUNTERCLAIM THEREIN.

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          IN WITNESS WHEREOF, the undersigned has caused this Guarantee to be
duly executed and delivered by its duly authorized officer as of the day and
year first above written.

                                        NEW CENTURY FINANCIAL CORPORATION


                                        By:        /s/  Patrick Flanagan
                                           -------------------------------------
                                           Title:  Executive Vice President


                                        Address for Notices:

                                        18400 Von Karman, Suite 1000
                                        Irvine, CA  92612
                                        Telex:
                                              ---------------
                                        Fax: (949) 440-7033