| George Arthur Brethen | |
| Constituency Mp: | Peterborough East |
| Parliament: | Canadian |
| Predecessor: | John Albert Sexsmith |
| Successor: | Riding redistributed between Hastings—Peterborough and Peterborough West |
| Term Start: | 1921 |
| Term End: | 1925 |
| Birth Date: | August 29, 1877 |
| Birth Place: | Norwood, Ontario, Canada |
| Death Date: | January 31, 1968 |
| Nationality: | Canadian |
| Party: | Progressive Party |
| Occupation: | farmer |
George Arthur Brethen (born August 29, 1877 in Norwood, Ontario, Canada-died January 31, 1968) was a Canadian politician and farmer. He was elected to the House of Commons of Canada as a Member of the Progressive Party in the 1921 election to represent the riding of Peterborough East. He was defeated in the 1925 election in the riding of Hastings—Peterborough.