Lee Daniels says he knows exactly who is responsible for Mo'Nique getting blackballed from Hollywood -- Mo'Nique.

The famed director tells us it's past time for Mo'Nique to quit bitching and blaming Tyler PerryOprah and himself for shutting her out of the movie biz. Especially because Lee played a key role in her winning an Oscar.

As we reported ... Mo'Nique went after Lee, Tyler and O during a stand-up special last year at the Apollo Theater -- telling the Hollywood power trio they "can suck my d***, if I had one!"

Lee fired back at her on "Raq Rants" ... telling Raquel no one should confuse the Mo situation with what went down with Damon Dash. He insists he gave Mo'Nique as much as she gave him when they made "Precious" -- comparing it to "making love without having sex."

It's clear there's ZERO love now. He says Mo'Nique is playing herself, and it would be best for her to quit complaining -- but that's putting it nicely. Watch how he actually said it.

And check out the full interview to see what he said about Diana Ross, Billie Holiday, and something he's never talked about before ... his sexuality.