The 2019–20 Grambling State Tigers men's basketball team represented Grambling State University in the 2019–20 NCAA Division I men's basketball season. The Tigers, led by third-year head coach Donte Jackson, played their home games at the Fredrick C. Hobdy Assembly Center in Grambling, Louisiana as members of the Southwestern Athletic Conference. They finished the season 17–15, 11–7 in SWAC play to finish in a three-way tie for fourth place. They lost in the quarterfinals of the SWAC tournament to Texas Southern.