The men are accused of taking a paparazzo's camera in Beverly Hills, Calif., on Sept. 5. The incident remains under investigation by Beverly Hills police, who did not immediately return a phone message seeking comment.
Williams, who was arrested at a Los Angeles-area courthouse when he appeared for an arraignment in a separate assault case, faces up to seven years in prison if convicted.
Knight, 49, was arrested in Las Vegas. Police said he was taken into custody without incident.
A phone message for Anthony Brooklier, an attorney who has represented Knight, was not immediately returned. An email message sent to Williams' agent, Chris Smith, was not immediately returned.
Williams, 43, has starred in several comedy specials and appeared in films such as First Sunday and Friday After Next.
Knight was shot and wounded in a West Hollywood, Calif., nightclub about a week and a half before the incident with the photographer. He founded Death Row Records, one of rap's leading labels in the 1990s, but later declared bankruptcy and the company was auctioned off.