Main Street Capital Announces Third Quarter 2008 Earnings Release and Conference Call Schedule

    HOUSTON, Oct. 23 /PRNewswire-FirstCall/ - Main Street Capital Corporation
(Nasdaq: MAIN) ("Main Street") today announced the release of its third
quarter 2008 financial results on Monday, November 10, 2008 after the
financial markets close.  In conjunction with the third quarter 2008 earnings
release, Main Street has scheduled a conference call, which will also be
broadcast via webcast, for Tuesday, November 11, 2008 at 10:00 a.m. Eastern
Time.

    What:   Main Street Capital Third Quarter 2008 Earnings Conference Call
    When:   Tuesday, November 11, 2008 -- 10:00 a.m. Eastern Time
    How:    Live via phone -- By dialing 303-262-2053 or 800-218-4007 and
            asking for the Main Street Capital call at least 10 minutes prior
            to the start time -- or via webcast by logging into the investor
            relations section of the company's web address below.
    Where:  http://www.mainstcapital.com

A telephonic replay of the conference call will be available through Wednesday, November 19, 2008 and may be accessed by dialing 303-590-3000 and using the passcode 11121586#. An audio archive will also be available on the investor relations section of the company's website at http://www.mainstcapital.com shortly after the call and will be accessible for approximately 90 days. For more information, please contact Gus Okwu at DRG&E at 404-532-0086 or email gokwu@drg-e.com.

ABOUT MAIN STREET CAPITAL CORPORATION

Main Street (http://www.mainstcapital.com) is a principal investment firm that provides long-term debt and equity capital to lower middle market companies. Main Street's investments are generally made to support management buyouts, recapitalizations, growth financings and acquisitions of companies that operate in diverse industry sectors and generally have annual revenues ranging from $10 to $100 million. Main Street seeks to partner with entrepreneurs, business owners and management teams and generally provides "one-stop" financing alternatives to its portfolio companies.

     Contacts:
     Main Street Capital Corporation
     Todd A. Reppert, President and CFO
     treppert@mainstcapital.com
     713-350-6000

     Dennard Rupp Gray and Easterly, LLC
     Ken Dennard
     ksdennard@drg-e.com / 713-529-6600
     Augustine Okwu
     gokwu@drg-e.com / 404-532-0086

SOURCE Main Street Capital Corporation