Antonio Siddi was an Italian athlete who competed at the 1948 and 1952 Olympics, helping Italy win a bronze medal in the 4x100 relay in 1948. Siddi was a versatile runner, competing in the sprints and up to the 800 metres, as well as the 400 hurdles and the high jump and long jump.

In 1950 Siddi won a silver medal at the European Championships with the Italian 4x400 relay team. He won three medals at the 1951 Mediterranean Games, with golds in the 200 and 4x1 relay. He had actually won four gold medals in 1949 at the forerunner of the Mediterranean Games, which are no longer considered official, winning in the 100, 200, 400, and long jump. He won 17 international caps from 1946-52. Domestically Siddi won six Italian titles: 100 (1950), 200 (1948), and 400 (1947, 1949, 1951, 1953).

Personal Bests: 100 – 10.5 (1949); 400 – 47.2 (1949).