The Cougars did it without their leading scorer, DaVonte Lacy. Lacy had an appendix attack early Saturday morning and will miss the conference opener against Arizona next Thursday.
D.J. Shelton recorded his second double-double of the season with 14 points and 13 rebounds for Washington State (7-5) who shot 88 percent from the field in the second half.
Washington State got out to an early 21-3 lead and never trailed in the game. It held Mississippi Valley State (3-8) to just one basket in the early run as they started the game 1-for-16 from the field. The Delta Devils went eleven minutes without a score in the first half.
Washington State continued the rout in the second half, outscoring MVSU 48-18 in the paint.
The Cougars had their best shooting game of the season at 60 percent (33 of 55) from the field. The Delta Devils shot only 27 percent for the game and did not have a player in double figures.