James Arthur Mathewson

James Arthur Mathewson (June 26, 1890 – August 23, 1963) was a Canadian politician.

Born in Montreal, Quebec, Mathewson received a Bachelor of Arts degree in 1912 and a Bachelor of Civil Law degree in 1917 from McGill University. He was called to the Quebec Bar in 1917. He was a captain in the 42nd Battalion Royal Highlanders of Canada during World War I. After the war, he was a lawyer in Montreal. He was created a King's Counsel in 1926.

He was a member of the Montreal City Council for Saint-André from 1926 to 1930. He ran unsuccessfully for mayor in 1930 losing to Camillien Houde. He was the Liberal member of the Legislative Assembly of Quebec for Montréal–Notre-Dame-de-Grâce from 1939 to 1948. He was treasurer of Quebec from 1939 to 1944.

He was awarded an honorary doctorate degree from McGill University in 1943.