The Golden Flashes (7-1), who are 5-0 at home this season, went on a 16-1 run in the last 7:04 of the first half to turn a four-point deficit into a 30-19 lead at the break.
The Warhawks (2-6) closed the gap to 34-28 with 16:38 to go, but Guyton answered with a 3-pointer. He was 5 of 7 from beyond the arc for Kent State, which made 10 of 21 3-pointers.
Greene was 7 of 8 from the field and 3 of 3 from the free-throw line.
Hugh Mingo scored 16 points and was the only player in double figures for the Warhawks, who are 0-4 on the road.
Louisiana-Monroe shot 36.4 percent from the field in the first half (8 of 22), improving to 55.6 percent (15 of 27) in the second. That wasn't enough as Kent State shot 49.1 percent (26 of 53) for the game.