The 2023–24 Western Illinois Leathernecks men's basketball team represented Western Illinois University during the 2023–24 NCAA Division I men's basketball season.

The Leathernecks, led by first-year head coach Chad Boudreau, played their home games at Western Hall in Macomb, Illinois as first-year members of the Ohio Valley Conference.

[1] They were defeated by St. Thomas in the quarterfinals of the Summit League tournament.

[3] On April 7, 2023, it was announced that head coach Rob Jeter would be leaving the school to take the head coaching position at Southern Utah.

[4] After being named interim head coach immediately following Jeter's departure, Chad Boudreau was named the team's permanent head coach on April 13.