The 2021 Lamar Cardinals football team represented Lamar University in the 2021 NCAA Division I FCS football season as a member of the Western Athletic Conference. The Cardinals were led by second-year head coach Blane Morgan and played their home games at Provost Umphrey Stadium. The game against North American University is not included in the Western Athletic Conference or AQ7 standings because it was classed as an exhibition game and was not countable due to NCAA policies.