Exhibit 31.1

CERTIFICATION  Pursuant to Section 302 of The Sarbanes-Oxley Act of 2002

I, David Gladstone, certify that:

1.     I
have reviewed this quarterly report on Form 10-Q of Gladstone Investment Corporation;

2.     Based
on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in
light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;

3.     Based
on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition,
results of operations and cash flows of the registrant as of, and for, the periods presented in this report;

4.     The
registrant's other certifying officer and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act
Rules 13a-15(e) and 15d-15(e)) and internal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and 15d-15(f))
for the registrant and have:

a)    Designed
such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material
information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being
prepared;

b)    Designed
such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide
reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles;

c)     Evaluated
the effectiveness of the registrant's disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure
controls and procedures, as of the end of the period covered by this report based on such evaluation; and

d)    Disclosed
in this report any changes in the registrant's internal control over financial reporting that occurred during the registrant's most recent fiscal quarter (the
registrant's fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrant's internal control over financial
reporting; and

5.     The
registrant's other certifying officer and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrant's
auditors and the audit committee of registrant's board of directors (or persons performing the equivalent functions):

a)    All
significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely
affect the registrant's ability to record, process, summarize and report financial information; and

b)    Any
fraud, whether or not material, that involves management or other employees who have a significant role in the registrant's internal control over financial reporting.

Date:
October 31, 2007

|/s/DAVID GLADSTONEDavid Gladstone Chief Executive Officer and Chairman of
the
Board of Directors |  | 
|------------------------------------------------------------------------------------------------ |  | 

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