Kenneth Leroy Roberts Jr. (born July 25, 1973, in Mountain View, California) is an American former professional Grand Prix motorcycle road racer who won the 500cc Grand Prix Motorcycle Racing Championship in 2000, after finishing runner-up in 1999.

He joins his father Kenny Roberts as the only father-son duo to have won 500cc World Championships.

By 1993, he made his World 500cc debut at the Laguna Seca Raceway event, and was a full-time 250cc racer for 1994 and 1995 with the Marlboro-Yamaha team.

His debut race with Suzuki in Malaysia resulted in a surprise win, defeating the reigning champion, Michael Doohan.

With Crivillé failing to regain his form, Roberts' main challenge came from Valentino Rossi, a rookie rider fresh from winning the 250cc title.

With Rossi dominating the series to win the title, Roberts only managed a single podium and finished the season in disappointing 11th position.

At the end of 2005, Suzuki decided not to renew Roberts' contract and opted for a younger rider in Chris Vermeulen.

Honda provided the RC211V V5 engine with the frame being designed by Team Roberts and the bike subsequently named KR211V.

After only 4 points in the first part of the season, Kenny Jr. stopped racing midseason, replaced by his brother Kurtis, and never returned in 2007.