50 Cent Slams Oprah for Only 'Going After Black Men' Accused of Sexual Assault

50 Cent thinks Oprah is targeting famous black men accused of being sexual predators ... but gives white guys in the same boat a pass.

The rapper took to Instagram to call O out, saying ... "I don’t understand why Oprah is going after black men. No Harvey Weinstein, No Epstein, just Micheal Jackson and Russell Simmons this sh*t is sad."

Fiddy's referring to the media mogul's upcoming #MeToo documentary featuring Drew Dixon, one of the women who's accused Russell Simmons of sexual misconduct, along with her 'After Neverland' interview of Jackson's accusers, Wade Robson and James Safechuck.

50 also roped in Oprah's close friend Gayle King -- who conducted R. Kelly's disastrous TV interview after "Surviving R. Kelly" renewed outrage about his behavior -- adding ... "Gale hit R Kelly with the death blow documentary," and he claims, "These documentary’s are publicly convicting their targets, it makes them guilty till proven innocent."

The rapper then shared a photo showing images of Bill Cosby, Jeffrey Epstein, Kevin Spacey, Harvey Weinstein, R. Kelly and Donald Trump ... with "Jail" written on the black men and "Walk" on the white men. He captioned it, "You think Oprah don’t notice how this sh*t is playing out?"

Of course, 50 and Oprah have feuded in the past ... when she criticized lyrics in rap music and he disparaged her audience. They seemingly smoothed things over in a 2012 TV interview, but with Fiddy ... any beef can be renewed.