CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
We have issued our reports dated March 10, 2010 with respect to the consolidated financial statements, Schedule 12-14 and the schedule of Senior Securities of Main Street Capital Corporation contained in Post- Effective Amendment No. 1 to the Registration Statement and Prospectus. We consent to the use of the aforementioned reports in Post- Effective Amendment No. 1 to the Registration Statement and Prospectus, and to the use of our name as it appears under the caption "Independent Registered Public Accounting Firm".
/s/ GRANT THORNTON LLP
Houston,
Texas
April 19, 2010