Alexander McLagan Ross (April 20, 1829 – March 31, 1901) was a Canadian banker and politician, who served as a Member of the Legislative Assembly of Ontario for Huron West from 1875 to 1890 as a Liberal member.
He was born in Dundee, Scotland, the son of Colin Ross and Elizabeth McLagan, and came to Upper Canada with his family in 1834.
In 1858, he was named treasurer for the united counties of Huron and Bruce.
He continued to serve as treasurer for Huron from 1866 to 1883 after the two counties were split.
He was a lieutenant-colonel in the local militia and served during the Fenian raids.