"I was really pleased with how our team performed tonight," UCLA head coach Ben Howland said. "We did a good job on both ends of the floor. We came out and missed our first few shots, but then got on a roll offensively."
Brock Motum scored 18 as the only player in double-figures for Washington State (14-15, 6-11).
The Bruins played inspired, particularly on the defensive end, scoring 22 points off turnovers and holding the Cougars to 38.1 percent shooting.
UCLA won for the seventh straight time in the series.
"Tonight we had an inside presence," David Wear said. "Josh Smith was doing well, and we were crashing the boards. I'm proud of the way we came together. We had 26 assists as a team."
The Bruins led at halftime, 38-19, and outscored the visiting Cougars by a 40-27 margin in the second half. UCLA's 19-point halftime cushion was its largest of the conference season.
UCLA's 32-point margin of victory was its largest of the Pac-12 Conference season and the biggest win over a conference opponent since a 97-63 home win over Stanford on Jan. 31, 2009.
The Bruins will play their final regular-season game against Washington on Saturday at the Los Angeles Sports Arena. The game is slated for an 11 a.m. tip-off and will be televised live on CBS.