Kevin Pangos and Elias Harris each scored 19 points to lead Gonzaga, which improved to 94-7 all-time at McCarthey Athletic Center in Spokane.
Butler sophomore Erik Fromm led the Bulldogs with a career-high 16 points. Fromm, who made his first career start, shot 4-for-6 from three-point range and 6-for-11 from the floor.
The 6-9 forward kept the Bulldogs in the game with his long-range shooting, hitting a trey to pull BU within 39-33 early in the second half.
Gary Bell answered with a three-pointer to trim the Gonzaga lead to 42-36 with 16:25 remaining.
"Fromm played great again, he's really coming along," Stevens said. "We needed to find him a couple more times instead of forcing the ball through other people."
Throughout the rest of the second half, Butler clamped down on defense and was able to get enough stops to stay in the game. However, the Bulldogs couldn't convert on the other end enough and eventually Gonzaga pulled away. BU made 2 of its last 12 field goal attempts as Gonzaga iced the game at the foul line.
Sophomore Khyle Marshall was the other Butler player in double figures with 10 points, including a highlight-reel lob dunk on a pass from freshman Roosevelt Jones.
Freshman Kameron Woods scored eight points and Jones chipped in seven points and seven rebounds.
Fromm scored Butler's first five points as Butler led at times early in the game. BU would lead 10-9 before a 6-0 run gave Gonzaga a 15-10 lead at the 11:38 mark. The Gonzaga Bulldogs would not trail again. Butler was within 29-22 before Pangos made a three-pointer and Harris scored to make it 34-22. Gonzaga would go on to build a 38-28 halftime lead.
Butler and Gonzaga were even in field goals made (24) and turnovers (10). BU crashed the boards for 15 offensive rebounds, but Stevens was hoping to convert more putbacks.
"You have got to finish those," Stevens said. "We got knocked off our spot a bit but we have to be strong and finish them. The guys did play hard to get those offensive rebounds, but we have got to be better offensively."
The Bulldogs (5-7) will travel to Stanford (10-1) at 9 p.m. Thursday.
The game will be televised nationwide on Fox Sports Net.