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                                                                     EXHIBIT 8.1


                      [JENKENS & GILCHRIST LETTERHEAD]



                                May 12, 1998



Southside Bancshares, Inc.
1201 S. Beckman
Tyler, Texas  75701

         Re:     FEDERAL INCOME TAX OPINION REQUIRED UNDER ARTICLE VI, SECTION
                 601(B) OF THAT AMENDED AND RESTATED TRUST AGREEMENT (THE
                 "TRUST AGREEMENT") DATED MAY __, 1998 AMONG SOUTHSIDE
                 BANCSHARES, INC. ("COMPANY"), U.S. TRUST COMPANY OF TEXAS,
                 N.A. ("PROPERTY TRUSTEE"), WILMINGTON TRUST COMPANY ("DELAWARE
                 TRUSTEE"), SAM DAWSON AND LEE A. GIBSON ("ADMINISTRATIVE
                 TRUSTEES") AND HOLDERS (AS DEFINED IN THE TRUST AGREEMENT).

Gentlemen:

         Jenkens & Gilchrist, a Professional Corporation (the "Firm"), has
acted as special tax counsel to Southside Bancshares, Inc., a Texas
corporation, and Southside Capital Trust I (the "Trust Issuer") in connection
with the Registration Statement on Form S-2 (the "Registration Statement")
filed by the Company and the Trust Issuer with the Securities and Exchange
Commission (File Nos. 333-49889 and 333-49889-01) for the purpose of
registering under the Securities Act of 1933 (the "Act") the Trust Issuer's
Preferred Securities, the Company's Junior Subordinated Debentures, and the
Company's Guarantee with respect to the Preferred Securities.  You have
requested the opinions set forth in Section I hereof regarding the
characterization of the Trust for federal income tax purposes.  Section I of
this letter (the "Opinion Letter") contains the Firm's opinion.  Section II of
this Opinion Letter contains limitations on the opinion.  Except as otherwise
provided herein, all capitalized terms herein shall have the same meaning given
to them in the Registration Statement.
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Southside Bancshares, Inc.
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                                  I.  OPINION

         Based upon our analysis of the applicable authorities and subject to
the limitations set forth in Section II, the Firm is of the opinion that for
federal income tax purposes:

         1.      The Trust will be characterized as a grantor trust for U.S.
federal income tax purposes and not as an association subject to tax as a
corporation.

         2.      The discussion entitled "Certain Federal Income Tax
Consequences" in the Registration Statement, insofar as it relates to
statements of law or legal conclusions, is correct in all material respects.

                                II.  LIMITATIONS

         1.      Except as otherwise indicated, the opinions set forth in
Section I are based upon the Code and its legislative history, the regulations
promulgated thereunder, judicial decisions and current administrative rulings
and practices of the Internal Revenue Service, all as in effect on the date of
this Opinion Letter.  These authorities may be amended or revoked at any time.
Any such changes may or may not be retroactive with respect to transactions
entered into or contemplated prior to such changes and could significantly
alter the conclusions reached in this Opinion Letter.  There is no assurance
that legislative, judicial or administrative changes will not occur in the
future.  The Firm assumes no obligation to update or modify this Opinion Letter
to reflect any developments that may occur after the date of this Opinion
Letter.

         2.      The opinions set forth in Section I are not binding on the
Internal Revenue Service or the courts.  Additionally, the Firm's opinions set
forth herein are dependent upon the accuracy of the representations contained
in the representation letters signed by officers of the Company and provided to
the Firm.  The Firm has relied upon these representations and any inaccuracy
therein could adversely affect the opinions stated in Section I.  Also, the
Firm assumes that the representations will be accurate in all respects material
hereto as of the effective time of the Merger.

         3.      In connection with this Opinion Letter, the Firm has examined
originals or copies, certified or otherwise identified, of such documents and
records and such statutes, regulations and other instruments as it deemed
necessary or advisable for the purposes of the opinions set forth herein,
including (i) the Registration Statement on Form S-2 (File Nos. 333-49889 and
333-49889-01) and (ii) the form of Trust Agreement.  The Firm has assumed that
all signatures on all documents presented to it are genuine, that all documents
submitted to it as originals are accurate originals thereof, that all
information submitted to it is accurate and complete, and that all persons
executing and delivering originals or copies of documents examined by it are
competent to execute and deliver such documents.

         4.      The Firm is expressing its opinions only as to those matters
expressly set forth in Section I.  No opinion should be inferred as to any
other matters.
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Southside Bancshares, Inc.
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         5.      This Opinion Letter may be filed as an exhibit to the
Registration Statement.  Consent also is given to the reference to the Firm
under the caption "Legal Matters" in the Registration Statement as having
rendered the opinion in the "Certain Federal Income Tax Consequences" section
of such Registration Statement.  In giving this consent, the Firm does not
thereby admit that it comes into the category of persons whose consent is
required under section 7 of the Securities Act or the rules and regulations of
the Securities Exchange Commission promulgated thereunder.

                                        Respectfully submitted,

                                        JENKENS & GILCHRIST,
                                        a Professional Corporation



                                        By: /s/ PATRICK E. MITCHELL
                                           -----------------------------------
                                            Patrick E. Mitchell, for the Firm