The 2019–20 Western Illinois Leathernecks men's basketball team represented Western Illinois University in the 2019–20 NCAA Division I men's basketball season.

The Leathernecks, led by sixth-year head coach Billy Wright, played their home games at Western Hall in Macomb, Illinois, as members of the Summit League.

They failed to qualify for the Summit League tournament.

On March 3, 2020, the school announced that head coach Billy Wright's contract would not be renewed.

They upset top-seeded South Dakota State in the quarterfinals of the Summit League tournament,[3] before losing to North Dakota State in the semifinals.