“Everybody knows, yes it happened, I got slapped a year ago. I got smacked by this motherf****r,” he said.
Rock was slapped after making remarks about Smith’s wife, Jada Pinkett Smith, at the awards ceremony.
The 58-year-old comedian shared the story as part of his Netflix stand-up show Selective Outrage.
The special was streamed live from Baltimore on Saturday night.
“Will Smith played Muhammad Ali in a movie. Do you think I auditioned for that part? He played Muhammad Ali, I played Pookie in New Jack City,” he said.
Rock explained he did not retaliate on the night because of the way he was raised by his parents.
Rock also spoke about Meghan Markle, racism and abortion during his show.
“She’s complaining—I’m like, ‘What the f**k is she talking about? They’re so racist, they wanted to know how brown the baby was going to be?’” he said.
“That’s not racist. Cause even black people want to know how brown the baby gonna be. Sh*t. We check behind them ears.”
It is the first time the comedian has spoken about the incident at length. Smith, however, has spoken about the incident several times, and offered an apology for his behaviour.
Rock did not press charges after the incident. Meanwhile, the Academy banned Smith from attending the awards for 10 years.
The stand up special was held days before this year’s Academy Awards get underway in Los Angeles.