Exhibit 31.1



SECTION 302 CERTIFICATION



I, Douglas M. Polinsky, certify that:



| | 1. | I have reviewed this quarterly
report on Form 10-Q of Mill City Ventures III, Ltd.;
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| | 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;
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| | 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;
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| | 4. | The registrant’s other
certifying officer(s) 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:
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| | (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;
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| | (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;
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| | (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
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| | (d) | Disclosed in this report
any change in the registrant’s internal control over financial reporting that occurred during the registrant’s most
recent fiscal quarter that has materially affected, or is reasonably likely to materially affect, the registrant’s internal
control over financial reporting; and
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| | 5. | The registrant’s other
certifying officer(s) 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 the registrant’s board of directors (or persons performing
the equivalent functions):
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| | (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
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| | (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.
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|Date:  November 14, 2017 | /s/ Douglas M. Polinsky
|------------------------ | -----------------------
|                         | Chief Executive Officer