Luongo got on the scoresheet in the second half.
Neal Maupay put Brentford 1-0 ahead in the first half.
But QPR went ahead in an dramatic eight-minute spell when they grabbed three goals.
First, Luongo equalised, tapping in after Dan Bentley had saved from Luke Freeman.
Then Joel Lynch made it 2-1 when he helped Toni Leistner’s header into the net.
— QPR FC (@QPR)
Next, Nakhi Wells fired in Rangers’ third.
Brentford managed to pull a goal back in the 81st minute.
Romaine Sawyers teed up Henrik Dalsgaard to make it 3-2 but they couldn’t find an equaliser in the dieing stages.