Gary Hall Sr. (born c 1948) is a dentist from Phoenix, Arizona who became famous during the late 1960s and the 1970s, as an Olympic swimmer for the United States.

Hall first went to represent the United States in the 1968 Olympic Games held at Mexico City, Mexico.

At the 1972 Olympics in Munich, terrorism hit him close, as these were the games of the Munich Massacre. Nevertheless, he earned a silver medal during those games. His final Olympic appearance was at the 1976 Olympics in Montreal, Canada.

In 1981, he was inducted into the International Swimming Hall of Fame. Later on, he also became a local celebrity in Phoenix, as a dentist. He himself appears at his office's television ads, and he also appears on his office's billboard campaigns.

His son, Gary Hall Jr., has become a famous Olympic swimmer as well, getting various gold medals at the 2000 Olympics in Sydney, Australia. With his son's participation at the 2004 Olympics in Athens, Greece, the Halls became the first pair of father and son to make three Olympic appearances.