The 2020–21 Stephen F. Austin Lumberjacks basketball team represented Stephen F. Austin State University (SFA) during the 2020–21 NCAA Division I men's basketball season.

The Lumberjacks, led by fifth-year head coach Kyle Keller, played home games at the William R. Johnson Coliseum in Nacogdoches, Texas.

This season was the Lumberjacks' last as members of the Southland Conference; SFA is one of four schools, all from Texas, that will leave the Southland in July 2021 to join the Western Athletic Conference.

[1] The 2019–20 Stephen F. Austin Lumberjacks basketball team finished the season 28–3, 19–1 in Southland play to win the Southland regular season championship.

1 seed, they received a double-bye to the semifinals of the Southland tournament, however, the tournament was cancelled amid the COVID-19 pandemic.