| Open water swimming at the 1991 World Aquatics Championships | |
| Hostcity: | Perth, Australia |
| Events: | 2 |
| Next: | 1994 |
These are the results from the open water swimming competition at the 1991 World Aquatics Championships, which took place in Perth, Western Australia. The US led the competition.
| width=150 | Event | width=250 bgcolor=gold | Gold | width=250 bgcolor=silver | Silver | width=250 bgcolor=CC9966 | Bronze |
| 25 km | 5:01:45.78 | 5:03:18.81 | 5:08:53.35 |
| width=150 | Event | width=250 bgcolor=gold | Gold | width=250 bgcolor=silver | Silver | width=250 bgcolor=CC9966 | Bronze |
| 25 km | 5:21:05.53 | 5:25:16.67 | 5:28:22.74 |