John Archibald Calhoun (October 29, 1918 – January 21, 2000) was an American diplomat.

He later joined the U.S Foreign Service in 1941, and became the U.S. Vice Consul in Tijuana, Mexico, in 1942.

He attended the Naval School of Military Government at Princeton University and served in the U.S.

He was Minister Counselor for Political Affairs in Saigon, South Vietnam, from 1967 to 1968, during the Tet Offensive On July 8, 1969, he was nominated by President Nixon to be the Ambassador to Tunisia, where he served from 1969 to 1972.

Calhoun retired in 1972, after 31 years in the Foreign Service, upon returning to San Francisco.

He died on January 21, 2000, at the Marin General Hospital in San Rafael, California, of pneumonia and kidney failure.