Ennis was 6 of 9 from the field, including 5 of 8 from 3-point range, and matched his team-leading scoring average. Jennings pulled down seven rebounds for the 49ers (11-8, 7-1 Big West), who shot 57 percent from the floor and 58 percent from beyond the arc.
Irvine stayed close throughout the first half and trailed just 37-35 after Alex Young's 3-pointer a minute after halftime. But the Anteaters ran out of gas later in the second half, and Long Beach State's 15-3 run turned a 59-52 lead into 74-55.
Long Beach State has won its last five meetings with UC Irvine.
Colorado State graduate transfer John Gillon has chosen Syracuse, giving the Orange a potential starter at point guard entering the 2016-17 season.
DeSean Murray, who averaged 20.2 points as a sophomore at Presbyterian, will transfer to Auburn to play for coach Bruce Pearl.
Former Kentucky guard Ed Davender, the only Wildcat with at least 1,500 points and 400 assists, has died. He was 49.