Hawaii had a 21-point lead reduced to one at 46-45 with 9 minutes left in the second half, but the Rainbow Warriors pulled away with a 9-0 run.
Aaron Valdes had 10 points and 16 rebounds for Hawaii (5-2) and Mike Thomas grabbed 10 boards as the Rainbow Warriors held a 42-28 advantage on the glass.
Chavaughn Lewis scored 24 points for Marist (0-4) and Phillip Lawrence added 11. Lewis was 7 of 20 from the field and the Red Foxes made just 32.1 percent.
Marist has lost its first four games of the season in four of the last six years and dropped its first nine contests last season.
Hawaii will face East Carolina (3-2) on Wednesday in the fifth-place game.