Duncan Finlayson (ca 1796 – July 25, 1862) was a Scottish-born officer in the Hudson's Bay Company.
The son of John Finlayson, he was born in Dingwall, Scotland, and joined the Hudson's Bay Company (HBC) as a "writer" in 1815.
He recruited settlers for a proposed HBC colony at Puget Sound and sent 23 families to that area in 1841 in an unsuccessful attempt to counter American expansion in that area.
He travelled to Washington in 1848 with George Simpson and Henry Hulse Berens to negotiate land claims on behalf of the HBC.
Finlayson retired from service in June 1855 but was reappointed to the post in Lachine six months later.