Alexander Cowan (17 June 1775 – 13 February 1859) was a Scottish papermaker and philanthropist. He was a cousin and friend of Thomas Chalmers, the prominent Scottish minister. Through his business he was a friend and associate of the publisher Archibald Constable and, through Constable, an associate of Sir Walter Scott. Cowan owned and ran the huge Valleyfield paper-works in Penicuik in Midlothian.