1987–88 Washington State Cougars men's basketball team

The 1987–88 Washington State Cougars men's basketball team represented Washington State University for the 1987–88 NCAA Division I men's basketball season. Led by first-year head coach Kelvin Sampson, 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 12–15 overall in the regular season and 7–11 in conference play, sixth in the standings.

At the conference tournament's last quarterfinal, WSU upset third seed UCLA by two points. In the semifinal, the Cougars took second-seeded Oregon State to double overtime, but lost by six points.

Sampson was promoted to head coach in April 1987, and led the program for seven seasons.

Postseason results
!colspan=9 style=| Regular season

!colspan=9 style=| Pacific-10 Tournament