Swimming at the 2008 Summer Olympics – Women's 100 metre butterfly Semifinal 1 Semifinal 1

| Rank_ | Lane | Name_ | Nationality | Time_ |
|---|---|---|---|---|
| 1 | 7 | Lisbeth Trickett | Australia | 57.05 |
| 2 | 4 | Christine Magnuson | United States | 57.08 |
| 3 | 5 | Tao Li | Singapore | 57.54 |
| 4 | 8 | Jemma Lowe | Great Britain | 57.78 |
| 5 | 2 | Aurore Mongel | France | 58.46 |
| 6 | 1 | Alena Popchanka | France | 58.55 |
| 6 | 3 | Elaine Breeden | United States | 58.55 |
| 8 | 6 | Lize-Mari Retief | South Africa | 58.63 |