WHO'S DA MASTAH??? UFC middleweight badass Demian Maia ... because his new trainer is none other than BRUCE LEROY from the 80s cult classic "The Last Dragon."
Leroy -- real name Taimak (right) -- tells TMZ, he met Maia during a recent training session in New York ... and they immediately hit it off.
According to Taimak -- an accomplished martial artist in his own right -- Maia approached him in the gym, claiming he was a big "Last Dragon" fan (who isn't?) and the two kept in touch.
Now, Taimak says he and Maia have started to train together -- prepping Maia for his upcoming UFC 148 bout against Korean badass Kim Dong-Hyun, who's lost only ONE fight in his pro career.
As for training details -- Taimak was tight-lipped, not wanting to tip off Maia's Korean competition.