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                                                                     EXHIBIT 5.2

                                  May 20, 2003

Old Second Capital Trust I
c/o Old Second Bancorp, Inc.
37 River Street
Aurora, Illinois 60506-4172

          Re:  Old Second Capital Trust I
               --------------------------

Ladies and Gentlemen:

          We have acted as special Delaware counsel for Old Second Capital Trust
I, a Delaware statutory trust (the "Trust"), in connection with the matters set
forth herein. At your request, this opinion is being furnished to you.

          For purposes of giving the opinions hereinafter set forth, our
examination of documents has been limited to the examination of originals or
copies of the following:

          (a)  The Certificate of Trust of the Trust (the "Certificate of
               Trust"), as filed with the office of the Secretary of State of
               the State of Delaware (the "Secretary of State") on May 12, 2003;

          (b)  The Trust Agreement of the Trust, dated as of May 12, 2003 (the
               "Original Trust Agreement"), between Old Second Bancorp, Inc., a
               Delaware corporation (the "Company"), and Wilmington Trust
               Company, a Delaware banking corporation, as Delaware trustee (the
               "Delaware Trustee");

          (c)  The Registration Statement (the "Registration Statement") on Form
               S-3, including a preliminary prospectus (the "Prospectus"),
               relating to the Cumulative Trust Preferred Securities of the
               Trust representing preferred undivided beneficial interests in
               the Trust (each, a "Preferred Security" and collectively, the
               "Preferred Securities"), to be filed by the Company and the Trust
               with the Securities and Exchange Commission on or about May __,
               2003.

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Old Second Capital Trust I
May 20, 2003
Page 2

          (d)  A form of Amended and Restated Trust Agreement for the Trust, to
               be entered into among the Company, the Delaware Trustee and the
               other trustees of the Trust named therein (including the Exhibits
               thereto) (together with the Original Trust Agreement, the "Trust
               Agreement"), to be filed as an exhibit to the Registration
               Statement; and

          (e)  A Certificate of Good Standing for the Trust, dated May 19, 2003,
               obtained from the Secretary of State.

          Initially capitalized terms used herein and not otherwise defined are
used as defined in the Trust Agreement.

          For purposes of this opinion, we have not reviewed any documents other
than the documents listed in paragraphs (a) through (e) above. In particular, we
have not reviewed any document (other than the documents listed in paragraphs
(a) through (e) above) that is referred to in or incorporated by reference into
the documents reviewed by us. We have assumed that there exists no provision in
any document that we have not reviewed that is inconsistent with the opinions
stated herein. We have conducted no independent factual investigation of our own
but rather have relied solely upon the foregoing documents, the statements and
information set forth therein and the additional matters recited or assumed
herein, all of which we have assumed to be true, complete and accurate in all
material respects.

          With respect to all documents examined by us, we have assumed (i) the
authenticity of all documents submitted to us as authentic originals, (ii) the
conformity with the originals of all documents submitted to us as copies or
forms, and (iii) the genuineness of all signatures.

          For purposes of this opinion, we have assumed (i) that the Trust
Agreement will constitute the entire agreement among the parties thereto with
respect to the subject matter thereof, including with respect to the creation,
operation and termination of the Trust, and that the Trust Agreement and the
Certificate of Trust will be in full force and effect and will not be amended,
(ii) except to the extent provided in paragraph 1 below, the due organization or
due formation, as the case may be, and valid existence in good standing of each
party to the documents examined by us under the laws of the jurisdiction
governing its organization or formation, (iii) the legal capacity of natural
persons who are parties to the documents examined by us, (iv) that each of the
parties to the documents examined by us has the power and authority to execute
and deliver, and to perform its obligations under, such documents, (v) the due
authorization, execution and delivery by all parties thereto of all documents
examined by us, (vi) the receipt by each Person to whom a Preferred Security is
to be issued by the Trust (collectively, the "Preferred Security Holders") of a
Preferred Security Certificate for such Preferred Security and the payment for
such Preferred Security, in accordance with the Trust Agreement and the
Registration Statement, and (vii) that the Preferred Securities are
authenticated, issued and sold to the Preferred Security Holders in accordance
with the Trust Agreement and the Registration Statement. We have not
participated in the preparation of the Registration Statement or the Prospectus
and assume no responsibility for their contents.

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Old Second Capital Trust I
May 20, 2003
Page 3

          This opinion is limited to the laws of the State of Delaware
(excluding the securities laws of the State of Delaware), and we have not
considered and express no opinion on the laws of any other jurisdiction,
including federal laws and rules and regulations relating thereto. Our opinions
are rendered only with respect to Delaware laws and rules, regulations and
orders thereunder which are currently in effect.

          Based upon the foregoing, and upon our examination of such questions
of law and statutes of the State of Delaware as we have considered necessary or
appropriate, and subject to the assumptions, qualifications, limitations and
exceptions set forth herein, we are of the opinion that:

          1.    The Trust has been duly created and is validly existing in good
standing as a statutory trust under the Delaware Statutory Trust Act, 12 Del.
C.ss.3801, et. seq.

          2.    The Preferred Securities of the Trust have been duly authorized
by the Trust Agreement and, when executed and delivered to and paid for by the
purchasers thereof in accordance with the Trust Agreement and the Registration
Statement, will be duly and validly issued and, subject to the qualifications
set forth in paragraph 3 below, fully paid and non-assessable undivided
beneficial interests in the assets of the Trust

          3.    The Preferred Security Holders, as beneficial owners of the
Trust, will be entitled to the same limitation of personal liability extended to
stockholders of private corporations for profit organized under the General
Corporation Law of the State of Delaware. We note that the Preferred Security
Holders may be obligated to make payments as set forth in the Trust Agreement.

          We consent to the filing of this opinion with the Securities and
Exchange Commission as an exhibit to the Registration Statement. We hereby
consent to the use of our name under the heading "Legal Opinions" in the
Prospectus and any supplements thereto. In giving the foregoing consents, we do
not thereby admit that we come within the category of persons whose consent is
required under Section 7 of the Securities Act of 1933, as amended, or the rules
and regulations of the Securities and Exchange Commission thereunder.

                                        Very truly yours,


                                       /s/ Richards, Layton & Finger, P.A.
                                       -----------------------------------
                                          Richards, Layton & Finger, P.A.

DKD/jmb