| James Arthur Mathewson | |
| Office: | Member of the Legislative Assembly of Quebec for Montréal–Notre-Dame-de-Grâce |
| Predecessor: | District created in 1939 |
| Successor: | Paul Earl |
| Term Start: | 1939 |
| Term End: | 1948 |
| Birth Date: | 26 June 1890 |
| Birth Place: | Montreal, Quebec |
| Death Place: | Montreal, Quebec |
| Resting Place: | Mount Royal Cemetery |
| Party: | Liberal |
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[1] 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.