See main article: Swimming at the 2010 South American Games. The Women's 50m freestyle event at the 2010 South American Games was held on March 29, with the heats at 10:00 and the Final at 18:00.
| width=200 bgcolor=gold | Gold | width=200 bgcolor=silver | Silver | width=200 bgcolor=CC9966 | Bronze |
| Flávia Cazziolato | Arlene Semeco | Daynara de Paula |
| Standing records prior to the 2010 South American Games | |||||
|---|---|---|---|---|---|
| World record | 23.63 | Rome, Italy | 2 August 2009 | ||
| Competition Record | 25.82 | Buenos Aires, Argentina | 18 November 2006 | ||
| South American record | 24.76 | Rome, Italy | 1 August 2009 | ||
| Rank | Heat | Lane | width=250 | Athlete ! | width=100 | Result ! | Notes |
|---|---|---|---|---|---|---|---|
| 1 | 1 | 4 | 25.51 | Q CR | |||
| 2 | 3 | 4 | 25.82 | Q | |||
| 3 | 2 | 4 | 26.12 | Q | |||
| 4 | 3 | 3 | 26.34 | Q | |||
| 5 | 3 | 5 | 26.84 | Q | |||
| 6 | 2 | 5 | 26.94 | Q | |||
| 7 | 2 | 3 | 26.97 | Q | |||
| 8 | 1 | 5 | 27.04 | Q | |||
| 9 | 2 | 2 | 27.10 | NR | |||
| 10 | 3 | 6 | 27.15 | ||||
| 11 | 1 | 3 | 27.40 | ||||
| 12 | 1 | 6 | 28.07 | ||||
| 13 | 1 | 2 | 28.08 | ||||
| 14 | 3 | 7 | 28.22 | ||||
| 15 | 1 | 7 | 28.63 | ||||
| 16 | 3 | 1 | 28.70 | ||||
| 17 | 2 | 6 | 28.72 | ||||
| 18 | 3 | 2 | 28.93 | ||||
| 19 | 2 | 7 | 29.25 | ||||
| 20 | 2 | 1 | 29.28 | ||||
| Rank | Lane | width=250 | Athlete ! | width=100 | Result ! | Notes |
|---|---|---|---|---|---|---|
| 4 | 25.37 | CR | ||||
| 5 | 25.51 | |||||
| 3 | 25.94 | |||||
| 4 | 2 | 26.53 | ||||
| 5 | 6 | 26.65 | ||||
| 6 | 1 | 26.95 | ||||
| 7 | 7 | 27.20 | ||||
| 8 | 2 | 27.32 | ||||