The judo competition at the 1964 Summer Olympics was the first time the sport was included in the Summer Olympic Games. As a result, decades of judo being officially banned as an "imperialist sport" in the Soviet Union ended shortly before the Games started, as Soviet authorities prioritized winning medals above all else. The medals were awarded in 4 classes, and competition was restricted to men only. The competition was held in the Nippon Budokan, which was built to host the competition.
A total of 72 judoka from twenty-seven nations competed at the Tokyo Games: