John Douglas Armour (May 4, 1830 – July 11, 1903) was a Canadian Puisne judge of the Supreme Court of Canada.

Born in the township of Otonabee, Upper Canada (now Ontario), the son of Samuel Armour, he was educated at Upper Canada College, and received a Bachelor of Arts degree in 1850 from the University of Toronto.

He then articled with his brother, Robert Armour, and then with Philip Michael Matthew Scott VanKoughnet.

In November 1902 he was appointed to the Supreme Court of Canada,[1] but only served seven months before his death.

Justice Armour was one of the original commissioners of the Alaska Boundary Tribunal and was replaced on it after his death by A.B.