Her mother is of English, German and Cherokee ancestry. She has one older sister, Chimene Diaz, (born June 5, 1970, San Diego). She attended Long Beach Polytechnic High School at the same time as rapper Snoop Dogg.
At 16, she began her career as a fashion model. Diaz signed with top modeling agency Elite Model Management. After graduating from high school, then later she went to work in Japan and met video director Carlos de la Torre. On her return to the U.S., she moved in with him. For the next few years, her modeling took her around the world, working for contracts with major companies. She modeled for designers such as Calvin Klein and Levi's. She was featured on the cover of the July 1990 issue of Seventeen magazine.