The King of pop talked about the abuse in a special TV documentary which was watched by more than 14 million people on Monday.
He said his dad, who managed the group which made Michael a child star - The Jackson Five - often hit him and his brothers if they didn't get their dance steps right.
Boy called Blanket
The programme was made by journalist Martin Bashir, who did a famous interview with Princess Diana in 1995.
During his eight months with the superstar, he found out some other quite unusual things, including:
- He thinks he will live forever.
- He's nicknamed his baby boy (real name Prince Michael II) - Blanket, because blankets are a sign of someone's love.
- He climbs trees a lot and says that's where he gets the inspiration for his songs.
- He spent £3.6 million in one shop in Las Vegas, buying things like gold vases.
But some people are most worried about Jackson admitting he invites kids to stay over at his theme park home, Neverland. Sometimes they stay in his bedroom.
Wear masks