UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 6-K

Report of Foreign Private Issuer
Pursuant to Rule 13a-16 or 15d-16
of the Securities Exchange Act of 1934

For the month of: December, 2014

Platinum Group Metals Ltd.

(SEC File No. 001-33562)

Suite 788 — 550 Burrard Street, Vancouver BC, V6C 2B5, CANADA
Address of Principal Executive Office

Indicate by check mark whether the registrant files or will file annual reports under cover:

Form 20-F o Form 40-F x

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1): o

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7): o

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

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EXHIBIT INDEX

THE FOLLOWING DOCUMENTS ARE HEREBY INCORPORATED BY REFERENCE INTO THE REGISTRANT’S REGISTRATION STATEMENT ON FORM F-10 (FILE NO. 333-200824), AND TO BE A PART THEREOF FROM THE DATE ON WHICH THIS REPORT IS SUBMITTED, TO THE EXTENT NOT SUPERSEDED BY DOCUMENTS OR REPORTS SUBSEQUENTLY FILED OR FURNISHED:

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