SecProbe.io

April 1, 2014

Via E -mail
William B. Skoglund
Chairman and Chief Executive Officer
Old Second Bancorp, Inc.
37 South River Street
Aurora, IL 60506

Re: Old Second Bancorp,  Inc.
Amendment No. 2  to Registration Statement on Form S -1
Filed March 26 , 2014
  File No. 333 -193424

Dear Mr. Skoglund :

We have reviewed the above referenced filing  and have the following comments.  In
some of our comments, we may ask you to provide us with information so we may better
understand your disclosure.

Please respond to this letter by amending your registration statement and providing the
requested information.  If you do not believe our comments apply to your facts and
circumstances or do not believe an amendment is appropriate, please tell us why in your
response.

After reviewing any amendment to your registration statement and the information you
provide in response to these comments, we may have additional comments .

Amendment No. 2  to Registration Statement on Form S -1

Exhibit 23.1

Consent of Independent Registered Public Accounting Firm

1. The staff notes the consent refers to the report dated March 26, 2014 while the report in
the Form 10 -K is dated February 26 , 2014.  Please revise or advise.

We urge all persons who are responsible for the accuracy and adequacy of the disclosure
in the filing to be certain that the filing includes the information the Securities Act of 1933 and
all applicable Securities Act rul es require.   Since the company and its management are in
possession of all facts relating to a company’s disclosure, they are responsible for the accuracy
and adequacy of the disclosures they have made.

William B. Skoglund
Old Second Bancorp, Inc.
April 1, 2014
Page 2

 Notwithstanding our comments, in the event you request acceleration of the effective date
of the pending registration statement please provide a written statement from the company
acknowledging that:

 should the Commission or the staff, acting pursuant to delegated authority, declare the
filing effecti ve, it does not foreclose the Commission from taking any action with respect
to the filing;

 the action of the Commission or the staff, acting pursuant to delegated authority, in
declaring the filing effective, does not relieve the company from its full r esponsibility for
the adequacy and accuracy of the disclosure in the filing; and

 the company may not assert staff comments and the declaration of effectiveness as a
defense in any proceeding initiated by the Commission or any person under the federal
securities laws of the United States.

Please refer to Rules 460 and 461 regarding requests for acceleration.  We will consider a
written request for acceleration of the effective date of the registration statement as confirmation
of the fact that those requ esting acceleration are aware of their respective responsibilities under
the Securities Act of 1933 and the Securities Exchange Act of 1934 as they relate to the proposed
public offering of the securities specified in the above registration statement.  Ple ase allow
adequate time for us to review any amendment prior to the requested effective date of the
registration statement.

You may contact Chris Harley at (202) 551 -3695 or David Irving at (202) 551 -3321  if
you have questions regarding comments on t he financial statements and related matters.  Please
contact David Lin at (202) 551 -3552  or me at (202) 551 -3434  with any other questions.

Sincerely,

 /s/ Michael Clampitt

Michael Clampitt
Senior Counsel

cc: Via E -mail
 J. Douglas Cheatham
 Robert M. Fleetwood , Esq.