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                                                                    EXHIBIT 10.6

                      FIRST AMENDMENT TO LETTER AGREEMENT


    THIS FIRST AMENDMENT TO LETTER AGREEMENT (the "First Amendment") is made to
be effective as of February 2, 2001, and is by and between STERLING BANCSHARES,
INC., a Texas corporation (the "Borrower") and WELLS FARGO BANK MINNESOTA,
NATIONAL ASSOCIATION, formerly known as Norwest Bank Minnesota, National
Association, a national banking association (the "Bank").

    REFERENCE IS HEREBY MADE to that certain Letter Agreement dated February 2,
2000 (the "Agreement") made by and between the Borrower and the Bank. Terms not
otherwise defined in this First Amendment shall have the meanings ascribed to
them in the Agreement.

    WHEREAS, pursuant to the provisions of the Agreement, the Bank is the holder
of that certain  promissory note dated February 2, 2000 (the "Note") made by the
Borrower in the face amount of $20,000,000.00 and payable to Bank, which Note
evidences Borrower's obligations under that certain revolving line of credit
(the "Line") provided the Borrower by the Bank;

    WHEREAS, the Borrower has requested Bank to renew the Line and
correspondingly the Note for an additional twelve (12) months, to February 2,
2002; and,

    WHEREAS, Bank is willing to grant the Borrower's request, subject to the
provisions of this First Amendment;

    NOW, THEREFORE, in consideration of the premises and of the mutual
agreements herein, the parties agree as follows:

    1. Section 1 of the Agreement is hereby amended by changing the date
referenced therein as the "Termination Date" from "February 2, 2001" to
"February 2, 2002".

     2. Simultaneously with the execution of this First Amendment, the Borrower
shall execute and deliver to the Bank, in form and content acceptable to the
Bank, a new promissory note (which, for purposes of this First Amendment only,
shall be referred to herein as the "New Note") in the face amount of
$20,000,000.00. Upon the execution and delivery to the Bank of the New Note, the
outstanding principal of, and accrued but unpaid interest on, the Note shall be
deemed, respectively, the outstanding principal balance of, and accrued but
unpaid interest on, the New Note. The New Note shall replace, but shall not be
deemed payment or satisfaction of, the Note. Furthermore, the New Note shall be
subject to the terms and conditions of the Agreement as amended hereby; and, all
references in the Agreement to the "Note" shall be deemed to mean the New Note
as provided for herein.

     3. The Borrower hereby represents and warrants to the Bank as follows:

        A. The Agreement and Note constitute valid, legal and binding
           obligations owed by the Borrower to Bank, subject to no
           counterclaim, defense, offset, abatement or recoupment.

        B. As of the date of this First Amendment, no Event of Default under the
           Agreement has occurred and is continuing that, with the giving of
           notice or the passage of time or both, would be an Event of Default.
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Sterling Bancshares, Inc.
First Amendment To Letter Agreement
February 2, 2001

        C. The execution, delivery and performance of this First Amendment and
           the New Note by the Borrower are within its powers, have been duly
           authorized and are not in contravention of law or the terms of
           Borrower's articles of incorporation or by-laws, or of any
           undertaking to which the Borrower is a party or by which it is bound.

        D. As of the date of this First Amendment, all of the representations
           and warranties contained in Subsections A,B,G, I and J of Section 11
           of the Agreement are true and correct.

        E. As of the date of this First Amendment, the outstanding principal
           balance of the Note is $0.00.

     4. Except as expressly modified by this First Amendment, the Agreement
remains unchanged and in full force and effect.

IN WITNESS WHEREOF, the parties hereto have executed this First Amendment as of
the date first  written above.


                                     WELLS FARGO BANK MINNESOTA,
                                      NATIONAL ASSOCIATION

                                     By: /s/ William K. Klein
                                         --------------------------------------
                                     Its: Vice President
                                         --------------------------------------

THIS WRITTEN FIRST AMENDMENT REPRESENTS THE FINAL AGREEMENT BETWEEN THE PARTIES
AND MAY NOT BE CONTRADICTED BY EVIDENCE OF PRIOR, CONTEMPORANEOUS, OR SUBSEQUENT
ORAL AGREEMENTS OF THE PARTIES. THERE ARE NO UNWRITTEN ORAL AGREEMENTS BETWEEN
THE PARTIES.


STERLING BANCSHARES, INC.


By: /s/ George Martinez
   --------------------------------------
Its: Chairman
   --------------------------------------


            THE REMAINDER OF THIS PAGE IS INTENTIONALLY LEFT BLANK

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Sterling Bancshares, Inc.
First Amendment To Letter Agreement
February 2, 2001



ACKNOWLEDGMENT AND CONSENT:
--------------------------

The undersigned Guarantor hereby consents to the foregoing First Amendment, and
acknowledges that its Guaranty shall remain in full force and effect for so long
as the Line is outstanding. Pursuant to said Guaranty, the undersigned
absolutely and unconditionally guarantees, among other things, the payment of
all indebtedness evidenced by the Note, and all extensions, modifications,
renewals and replacements thereof.


STERLING BANCORPORATION, INC.

By: /s/ George Martinez
   -----------------------------
Its: Chairman
    ----------------------------

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