In March 2006, Lopez joined the cast of the daytime soap opera The Bold and the Beautiful playing the role of Dr. On July 18, 2006, he was released from his B&B contract.
In March 1987, he was cast as a guest star on the popular sitcom The Golden Girls as a Latino boy named Mario who faces deportation. Slater in the popular television sitcom Saved by the Bell, a role which lasted five years.
He was cast in a small part in the movie Colors (1988) as Felipe's friend. In 1997, Lopez starred as Olympic diver Greg Louganis in the television movie Breaking the Surface: The Greg Louganis Story.
In 1992, he hosted his first series on NBC called Name Your Adventure.
He hosts the serial tabloid Extra, as well as the MTV reality shows America's Best Dance Crew and MTV's Top Pop Group.
Mario Lopez was born on October 10, 1973 in San Diego, California, to Elvira, a telephone company clerk, and Mario Sr., who worked for the municipality of National City.