| John Ryan | |
| Fullname: | John Sydney Ryan |
| National Team: | Australia |
| Strokes: | Freestyle |
| Birth Date: | 23 February 1944 |
John Sydney Ryan (born 23 February 1944) is an Australian sprint freestyle swimmer of the 1960s, who won a bronze medal in the 4×100-metre freestyle relay at the 1964 Summer Olympics in Tokyo.
The West Australian combined with Bob Windle, David Dickson and Peter Doak to win Bronze in the 4 × 100 m freestyle relay, behind the United States and German teams, the first time this event had been contested at the Olympics. He also made the semifinals of the 100-metre freestyle. Ryan later took gold in the freestyle relayfreestyle relay at the 1966 Commonwealth Games in Kingston, Jamaica, and finished fourth in the 110-yard freestyle event.
He was educated at Wesley College in South Perth.