2021 Saint John's Johnnies football team

The 2021 Saint John's Johnnies football team represented Saint John's University as a member of the Minnesota Intercollegiate Athletic Conference (MIAC) during the 2021 NCAA Division III football season. Led by eighth-year head coach Gary Fasching, the Johnnies compiled an overall record of 11–1 with a mark of 8–0 in conference play. They finished first the MIAC's Northwoods Division and beat the, winners of the MIAC's Skyline Division in the MIAC Championship Game. As MIAC champion, Saint John's received and automatic bid to the NCAA Division III Football Championship playoffs, where the defeated in the first round before losing to  in the second round. The Johnnies played home games at Clemens Stadium in Collegeville, Minnesota.