1983–84 Washington State Cougars men's basketball team

The 1983–84 Washington State Cougars men's basketball team represented Washington State University for the 1983–84 NCAA Division I men's basketball season. Led by first-year head coach Len Stevens, the Cougars were members of the Pacific-10 Conference and played their home games on campus at Beasley Coliseum in Pullman, Washington.

The Cougars were 10–18 overall in the regular season and 4–14 in conference play, last in the standings. There was no conference tournament this season; it debuted three years later.

In early April 1983, Stevens was quickly promoted to head coach when George Raveling left Pullman for Iowa in the Big Ten. Prior to his two years as a Cougar assistant, Stevens was the head coach for three seasons at St. Martin's College in Lacey.

As they had two years earlier, WSU hosted the first two rounds in the West regional of the 53-team NCAA tournament at Beasley Coliseum. This was the third and most recent NCAA Tournament in Pullman; the Spokane Arena opened in 1995 and has hosted several times.

The court surface at Beasley Coliseum was tartan (polyurethane) for its first decade; a traditional hardwood floor debuted at the start of this season.