Eleven accusers, nine women and two men, took the stand over the searing six-week trial to describe sexual humiliation and violence.
After two days of deliberation, the jury found Kelly guilty on all the charges he was facing.
He is due to be sentenced on 4 May, and faces decades behind bars.
Prosecutors accused Kelly of using his fame and fortune to lure in victims with promises to help their musical careers. Several of his victims testified that they were underage when he sexually abused them.
The 54-year-old Grammy-winning singer, whose real name is Robert Sylvester Kelly, was found guilty of violating the Mann act, a law which bans interstate sex trafficking.
As the verdict was read out in court, Kelly sat still at his desk, according to reporters.
His facial expression was hidden by a face mask that he was required to wear due to the judge's pandemic rules.
The verdict comes 13 years after Kelly was acquitted of child pornography charges after a trial in the state of Illinois.