Exhibit 12.1








CERTIFICATION PURSUANT TO


RULE 13a-14 OF THE SECURITIES EXCHANGE ACT OF 1934,


AS ADOPTED PURSUANT TO


SECTION 302 OF THE SARBANES-OXLEY ACT OF 2002





I,
Craig Scherba, certify that:





1.
 I have reviewed
this annual report on Form 20-F for the fiscal year ended June 30,
2019 of NextSource Materials Inc.;





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(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:





(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 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





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 the
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: November 13,
2019
By:
/s/ Craig
ScherbaCraig
ScherbaChief Executive Officer
(principal executive officer)