| John Buchanan | |
| State Senate1: | Virginia |
| District1: | 40th |
| Term Start1: | January 12, 1972 |
| Term End1: | April 15, 1991 |
| Succeeded1: | Jack Kennedy |
| Party: | Democratic |
| Birth Name: | John Chalkley Buchanan |
| Birth Date: | 20 January 1911 |
| Birth Place: | Darwin, Virginia, U.S. |
| Death Place: | Wise, Virginia, U.S. |
| Alma Mater: | University of Virginia |
| Allegiance: | United States |
| Branch: | United States Navy |
| Serviceyears: | 1942–1946 |
| Battles: | World War II |
John Chalkley Buchanan (January 20, 1911 – April 15, 1991) was an American physician and politician who served in the Virginia Senate from his election in 1971 up to his death from cancer 20 years later. He chaired the Senate's General Laws committee.[1]