Mark Ruiz (born April 9, 1979 in Río Piedras, San Juan), is an Olympic diver from Puerto Rico. Ruiz represented the United States in the 2000 Olympic Games and the 2004 Olympic Games.
Ruiz took up diving at the age of 9. Upon a coach's suggestion, he moved to the U.S. at 12 to take advantage of the better training system. The move obviously paid off: During the spring nationals in 1999, he swept all three events (10-meter platform, 3-meter springboard and the non-Olympic event of 1-meter springboard), becoming the first diver since Greg Louganis in 1988 to accomplish this feat.
Ruiz also competes in synchronized diving (springboard and platform), which will have medal events for the first time in Sydney. Ruiz, a four-time national champion in the platform, has already qualified in the platform and 3-meter springboard. He and partner Rio Ramirez finished fourth in the 3-meter springboard at the 2000 World Cup.
Mark Ruiz was the individual state champion for diving all four years he competed at Dr. Phillips and was elected as a charter member of the Dr. Phillips Athletic Hall of Fame in 2000.