James Maclennan (March 17, 1833 – June 9, 1915) was a Canadian lawyer, politician, and Puisne judge of the Supreme Court of Canada.

[2] Born in the township of Lancaster, Upper Canada (now Ontario),[2] the son of Roderick Maclennan and Mary Macpherson, he received a Bachelor of Arts from Queen's University in 1849.

He practised law with Oliver Mowat in Toronto until 1888, when he was appointed to the Ontario Court of Appeal.

[2] In 1905, he was appointed to the Supreme Court of Canada and retired in 1909.

[3] Maclennan was married twice: to Elizabeth McGill in 1862 and to Mary L. Strange in 1909,[1] possibly children, but none surviving him.