Long Beach State (13-11, 7-1 Big West) led by three at the break but slowly built a lead that reached 16 on Travis Hammond's 3-pointer with 9:05 left.
Riverside trimmed the deficit to six with 3:10 left on Austin Quick's jumper, but Caffey made a pair from the line and McKay LaSalle (13 points) drilled a trey at 1:11 to push it back to a 12-point margin.
Caffey was 8 of 11 from the floor with five assists. David Samuels had 17 points on 7-of-14 shooting with 12 rebounds and two blocked shots. The 49ers have won six straight and propelled themselves to a tie at top of the Big West ledger with UC Davis.