World Peace grabbed Knight around the neck and struck him in the jaw with the knuckles of his mostly open hand. The incident happened Sunday, with 1:43 left in the first half of the Lakers' 98-97 win over the Pistons.
World Peace, the former Ron Artest, was also suspended seven games in April after an elbow to the head of Oklahoma City's James Harden. World Peace is notorious for his 86-game suspension in 2004 for his role in the brawl with Pistons fans in Detroit.
He also served a seven-game suspension in 2007 for his no-contest plea on a domestic violence charge.
World Peace will sit out as the Lakers' game against the Brooklyn Nets on Tuesday.