Gregor Richard Weiss (born February 18, 1941) is an American artistic gymnast. He represented the United States at the 1964 Summer Olympics, placing 7th in the team event and 59th in the individual all-around. He was a member of the U.S. team at the 1966 World Artistic Gymnastics Championships. In the NCAA, he competed for Penn State University and was the NCAA all-around champion in 1961. He was inducted into the U.S. Gymnastics Hall of Fame in 1991.