The 1920 Idaho Vandals football team represented the University of Idaho in the 1920 college football season. Idaho was led by first-year head coach Thomas Kelley in their penultimate season as an independent before joining the Pacific Coast Conference in 1922. The Vandals had one home game in Moscow on campus at MacLean Field, with one in Boise at the state fairgrounds. After coming up six points short at Oregon to start with two losses, Idaho won its last four games.