"I didn't think it would happen until I died or something," the 69-year-old said backstage after his induction.
Newman is among this year's eight inductees, which also includes rockers Heart and Rush, rap group Public Enemy, disco queen Donna Summer, bluesman Albert King, and producers Quincy Jones and Lou Adler.
Adler was inducted during Thursday's extravaganza by Richard "Cheech" Marin and Tommy Chong before being serenaded by Carole King with "So Far Away." Jack Nicholson was among Adler's fans in the crowd who gave the producer-mogul a standing ovation.
With his guitar around his neck, John Mayer inducted the late King into the Rock and Roll Hall of Fame before joining Gary Clark Jr. for King-tinged jam session.
"Albert King is why guitar-face was invented," said Mayer.
The event marks the first time since 1993 that the Cleveland, Ohio, institution has held its induction ceremony on the West Coast. It will be broadcast May 18 on HBO.