San Marino competed at the 2011 World Aquatics Championships in Shanghai, China between July 16 and 31, 2011.
Swimming
Main article: Swimming at the 2011 World Aquatics ChampionshipsSan Marino qualified 3 swimmers.
- Men
| Athlete | Event | Heats | Semifinals | Final | |||
|---|---|---|---|---|---|---|---|
| Time | Rank | Time | Rank | Time | Rank | ||
| Emanuele Nicolini | Men's 200 m Freestyle | 1:57.23 | 51 | did not advance | |||
| Men's 400 m Freestyle | 4:04.38 | 38 | did not advance | ||||
- Women
| Athlete | Event | Heats | Semifinals | Final | |||
|---|---|---|---|---|---|---|---|
| Time | Rank | Time | Rank | Time | Rank | ||
| Clelia Tini | Women's 50 m Freestyle | 27.15 | 41 | did not advance | |||
| Women's 100 m Freestyle | 59.50 | 49 | did not advance | ||||
| Simona Muccioli | Women's 100 m Butterfly | 1:06.45 | 45 | did not advance | |||
| Women's 200 m Butterfly | 2:22.03 | 31 | did not advance | ||||
Synchronised swimming
Main article: Synchronised swimming at the 2011 World Aquatics ChampionshipsSan Marino has qualified 2 athletes in synchronised swimming.
- Women
| Athlete | Event | Preliminary | Final | ||
|---|---|---|---|---|---|
| Points | Rank | Points | Rank | ||
| Elena Tini | Solo Technical Routine | 74.500 | 25 | Did not advance | |
| Solo Free Routine | 72.430 | 24 | did not advance | ||
| Cristina Nicolini Elena Tini |
Duet Technical Routine | 71.900 | 33 | Did not advance | |
| Duet Free Routine | 73.640 | 32 | did not advance | ||