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                                                                    EXHIBIT 10.1

                            FIRST AMENDMENT TO LEASE

I.   PARTIES AND DATE.

     This Amendment to Lease (the "Amendment") dated May 1, 2000, is by and
between THE IRVINE COMPANY ("Landlord"), and NEW CENTURY FINANCIAL CORPORATION,
a Delaware corporation ("Tenant").

II.  RECITALS.

     Landlord and Tenant entered into an undated lease ("Lease") for space in
two (2) buildings located at 340 Commerce ("340 Commerce Premises") and 350
Commerce, Suite 200 ("350 Commerce Premises") in Irvine, California.

     Landlord and Tenant each desire to modify the Lease to add approximately
25,277 rentable square feet of space within the building located at 350
Commerce, which is more particularly described on EXHIBIT A attached to this
Amendment and herein referred to as "Suites 100 and 250", extend the Lease Term
as to the 350 Commerce Premises (but not as to the 340 Commerce Premises),
adjust the Basic Rent, and make such other modifications as are set forth in
"III. MODIFICATIONS" next below.

III. MODIFICATIONS.

     A. Basic Lease Provisions. The Basic lease Provisions are hereby amended as
follows:

          1. Item 1 is hereby deleted in its entirety and substituted therefor
          shall be the following:

          "1. Premises: The Premises (more particularly described in Section
          2.1) consists of space located in two (2) buildings, commonly known
          as:

          "Building 1 -- 340 Commerce, Irvine, California
          "Building 2 -- 350 Commerce, Suites 100, 200 and 250, Irvine,
          California"

          2. Item 5 is hereby amended to extend the Term of this Lease as to the
          350 Commerce Premises (but not as to the 340 Commerce Premises) to
          that date (the "New Expiration Date") which is sixty (60) months, plus
          such additional days as may be required to cause this Lease to
          terminate on the final day of the calendar month, from and after the
          "Commencement Date for Suites 100 and 250" (as defined in Article
          III.C of this Amendment). The Term of this Lease as to the 340
          Commerce Premises shall not be extended to the New Expiration Date but
          instead shall expire on the original Expiration Date of the Lease.

          Subject to the terms and conditions of Section 3.3 of the Lease,
          Tenant shall have two (2) separate rights to extend the Term of this
          Lease for single extension periods of sixty (60) months each, one (1)
          of such periods as to the 350 Commerce Premises and Suites 100 and
          250, collectively. Tenant's right to extend the Term as to the 340
          Commerce Premises shall be as set forth in Section 3.3 of the Lease,
          without amendment. Consequently, Tenant's 9 to 12 month window for
          exercising of its option as to the 340 Commerce Premises contained in
          the first paragraph of Section 3.3(a) shall be not less than nine (9)
          months or more than twelve (12) months prior to the original
          Expiration Date of the Lease, and Tenant's 12 to 15 month "window" for
          requesting a rental quote from Landlord for the 340 Commerce Premises
          contained in the first paragraph of Section 3.3(b) shall be not less
          than twelve (12) months or more than fifteen (15) months prior to the
          original Expiration Date.

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     Notwithstanding the provisions of the last sentence of Section 3.3(c) of
     the Lease, Tenant's right to extend the Term provided in Section 3.3(a) as
     to the 350 Commerce Premises and as to Suites 100 and 250 shall extend from
     and after the new Expiration Date. Consequently, Tenant's 9 to 12 month
     "window" for exercising of its option as to the 350 Commerce Premises and
     Suites 100 and 250 contained in the first paragraph of Section 3.3(a) shall
     be not less than nine (9) months or more than twelve (12) months prior to
     the New Expiration Date, and Tenant's 12 to 15 month "window" for
     requesting a rental quote for the 350 Commerce Premises and for Suites 100
     and 250 from Landlord contained in the first paragraph of Section 3.3(b)
     shall be not less than twelve (12) months or more than fifteen (15) months
     prior to the New Expiration Date.

     3.   Item 6 is hereby amended by adding the following:

          "Basic Rent for Suites 100 and 250: Commencing on the Commencement
          Date of Suites 100 and 250, the Basic Rent for Suites 100 and 250
          shall be Forty Thousand Four Hundred Forty-Three Dollars ($40,443.00)
          per month, based on $1.60 per rentable square foot.

          Basic Rent for Suites 100 and 250 is subject to adjustment as follows:

          Commencing twelve (12) months following the Commencement Date of
          Suites 100 and 250, the Basic Rent for Suites 100 and 250 shall be
          Forty One Thousand Seven Hundred Seven Dollars ($41,707.00) per month,
          based on $1.65 per rentable square foot.

          Commencing twenty-four (24) months following the Commencement Date of
          Suites 100 and 250, the Basic Rent for Suites 100 and 250 shall be
          Forty Two Thousand Nine Hundred Seventy-One Dollars ($42,971.00) per
          month, based on $1.70 per rentable square foot.

          Commencing thirty-six (36) months following the Commencement Date of
          Suites 100 and 250, the Basic Rent for Suites 100 and 250 shall be
          Forty Four Thousand Two Hundred Thirty-Five Dollars ($44,235.00) per
          month, based on $1.75 per rentable square foot.

          Commencing forty-eight (48) months following the Commencement Date of
          Suites 100 and 250, the Basic Rent for Suites 100 and 250 shall be
          Forty Five Thousand Four Hundred Ninety-Nine Dollars ($45,499.00) per
          month, based on $1.80 per rentable square foot.

          Basic Rent for the 340 Commerce Premises and for the 350 Commerce
          Premises shall continue to be payable during Term as extended by this
          Amendment in accordance with the schedule set forth in Item 6 of Basic
          Lease provisions of the Lease."

     4.   Effective as of the Commencement Date for Suites 100 and 250, Item 8
     shall be deleted in its entirety and substituted therefor shall be the
     following:

          "8. Floor Area of Premises: Approximately 92,558 rentable square feet
          broken down as follows:

          340 Commerce Premises -- 53,360 rentable square feet

          350 Commerce Premises -- 13,921 rentable square feet

          Suites 100 and 250 -- 25,277 rentable square feet"

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          5. Item 9 is hereby deleted in its entirety and substituted therefor
          shall be the following:

             "9. Security Deposit: $183,266.00"

          6. Effective as of the Commencement Date for Suites 100 and 250, Item
          14 shall be deleted in its entirety and substituted therefor shall be
          the following:

             "14. Vehicle Parking Spaces: Three Hundred Seventy-Three (373)"

     B. Security Deposit. Concurrently with Tenant's delivery of this Amendment,
Tenant shall deliver the sum of Fifty Thousand Forty Nine Dollars ($50,049.00)
to Landlord, which sum shall be added to the Security Deposit presently being
held by Landlord in accordance with Section 4.3 of the Lease.

     C. Building 2 Signage. Landlord confirms and agrees that the non-exclusive
building-top sign on Building 2 referred to in the second sentence of Section
5.2 of the Lease is available for Tenant, and that, subject to that occupancy
requirement therein contained, Tenant shall have the right to install such
building-top signage in lieu of Tenant's existing exterior eyebrow sign on
Building 2. Further, the fourth sentence of Section 5.2 is amended to add "Loan
Trader" to the list of names which may appear on Tenant's building-top signage
(provided that such entity is in fact conducting business within the Premises).

     D. Floor Plan of Suites 100 and 250. As used herein, "Suites 100 and 250"
shall mean the space described on Exhibit A attached to this Amendment. From and
after the date of this Amendment, Suites 100 and 250 collectively with the 340
Commerce Premises described on EXHIBIT A attached to the Lease and the 350
Commerce Premises described on EXHIBIT A-1 attached to the Lease, shall
constitute the "Premises" as defined in Section 2.1 of the Lease.

     E. Tenant Improvements. Landlord hereby agrees to complete the Tenant
Improvements for Suites 100 and 250 in accordance with the provisions of Exhibit
X-1, Work Letter, attached to this Amendment. Landlord estimates that this Lease
as to Suites 100 and 250 shall commence on or about July 14, 2000 (the
"Estimated Commencement Date for Suites 100 and 250"), but Landlord makes no
representation or warranty as to such date, and this Lease as to Suites 100 and
250 shall commence on the actual Commencement Date for Suites 100 and 250, as
hereinafter defined. As used herein, "Commencement Date for Suites 100 and 250"
shall mean the earlier of (a) Landlord's tender of possession of Suites 100 and
250 to Tenant with the "Tenant Improvements" (as defined in the Work Letter
attached hereto) for Suites 100 and 250 substantially completed but for minor
punch list items, or (b) the date Tenant acquires possession or commences use of
Suites 100 and 250 is tendered to Tenant, the parties shall memorialize on a
form provided by Landlord the actual Commencement Date for Suites 100 and 250,
provided that Tenant's failure to execute that form shall not affect the
validity of Landlord's determination of said date.

     If for any reason other than "Tenant Delays" (as defined in the Work Letter
attached to this Amendment) or other matters beyond Landlord's reasonable
control, the Commencement Date for Suites 100 and 250 has not occurred by the
date that is ninety (90) days following the Estimated Commencement Date for
Suites 100 and 250, then Tenant may, by written notice to Landlord given at any
time thereafter but prior to the actual occurrence of the Commencement Date for
Suites 100 and 250, elect to terminate this Amendment. Notwithstanding the
foregoing, if at any time during the construction period, Landlord reasonably
believes that the Commencement Date for Suites 100 and 250 will not occur on or
before ninety (90) days following the Estimated Commencement Date for Suites 100
and 250, Landlord shall notify Tenant in writing of such fact and of a new
outside date on or before which the Commencement Date for Suites 100 and 250
will occur, and Tenant must elect within ten (10) days of receipt of such notice
to either terminate this Amendment or waive its right to terminate this
Amendment provided the Commencement Date for Suites 100 and 250 occurs on or
prior to

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the new outside date established by Landlord in such notice to Tenant. Tenant's
failure to elect to terminate this Amendment within such ten (10) day period
shall be deemed Tenant's waiver of its right to terminate this Amendment as
provided in this paragraph as to the previous outside date, but not as to the
new outside date established by said notice.

     F. Right of First Refusal. Section 2.4 Right of First Refusal of the Lease
is hereby deleted in its entirety and shall have no further force or effect.

IV.  GENERAL.

     A. Effect of Amendments. The Lease shall remain in full force and effect
except to the extent that it is modified by this Amendment.

     B. Entire Agreement. This Amendment embodies the entire understanding
between Landlord and Tenant with respect to the modifications set forth in "III.
MODIFICATIONS" above and can be changed only by a writing signed by Landlord and
Tenant.

     C. Counterparts. If this Amendment is executed in counterparts, each is
hereby declared to be an original; all, however, shall constitute but one and
the same amendment. In any action or proceeding, any photographic, photostatic,
or other copy of this Amendment may be introduced into evidence without
foundation.

     D. Defined Terms. All words commencing with initial capital letters in this
Amendment and defined in the Lease shall have the same meaning in this Amendment
as in the Lease, unless they are otherwise defined in this Amendment.

     E. Corporate and Partnership Authority. If Tenant is a corporation or
partnership, or is comprised of either or both of them, each individual
executing this Amendment for the corporation or partnership represents that he
or she is duly authorized to execute and deliver this Amendment on behalf of the
corporation or partnership and that this Amendment is binding upon the
corporation or partnership in accordance with its terms.

     F. Attorneys' Fees. The provisions of the Lease respecting payment of
attorneys' fees shall also apply to this Amendment.

V.  EXECUTION.

     Landlord and Tenant executed this Amendment on the date as set forth in "I.
PARTIES AND DATE." above.

LANDLORD:                              TENANT:

THE IRVINE COMPANY       [Legal            NEW CENTURY FINANCIAL CORPORATION,
                        Approval           a Delaware corporation
                          Seal]

By /s/ ROBERT E. WILLIAMS, JR.             By /s/ Edward F. Gotschall
       -----------------------                    ----------------------
       Robert E. Williams, Jr., President
       Irvine Industrial Company, a        Title  Vice Chairman
       division of The Irvine Company             ----------------------

By /s/ NANCY E. TRUJILLO                   By /s/ Stegios Theologides
       -----------------------                    ----------------------
       Nancy E. Trujillo,
       Assistant Secretary                 Title  Secretary
                                                  ----------------------

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