Swimming at the 2011 World Aquatics Championships – Women's 50 metre butterfly
The women's 50 metre butterfly competition of the swimming events at the 2011 World Aquatics Championships was held on July 29 with the heats and the semifinals and July 30 with the final.
Records
Prior to the competition, the existing world and championship records were as follows.| Name | Nation | Time | Location | Date | |
| World record Championship record | Therese Alshammar | 25.07 | Rome | July 31, 2009 |
Results
Heats
51 swimmers participated in 7 heats.| Rank | Heat | Lane | Name | Nationality | Time | Notes |
| 1 | 7 | 4 | Therese Alshammar | 25.68 | Q | |
| 2 | 7 | 5 | Jeanette Ottesen | 25.88 | Q | |
| 3 | 7 | 7 | Dana Vollmer | 25.98 | Q | |
| 4 | 6 | 6 | Lu Ying | 26.16 | Q | |
| 5 | 5 | 4 | Sarah Sjöström | 26.17 | Q | |
| 6 | 6 | 2 | Christine Magnuson | 26.20 | Q | |
| 7 | 6 | 4 | Inge Dekker | 26.32 | Q | |
| 8 | 5 | 3 | Mélanie Henique | 26.37 | Q | |
| 9 | 6 | 3 | Yuka Kato | 26.37 | Q | |
| 10 | 5 | 6 | Triin Aljand | 26.43 | Q | |
| 11 | 7 | 6 | Tao Li | 26.43 | Q | |
| 12 | 7 | 3 | Marleen Veldhuis | 26.50 | Q | |
| 13 | 5 | 5 | Marieke Guehrer | 26.59 | Q | |
| 14 | 5 | 7 | Daynara de Paula | 26.60 | Q | |
| 15 | 7 | 1 | Vanessa Mohr | 26.69 | Q | |
| 16 | 6 | 7 | Amit Ivry | 26.83 | Q | |
| 17 | 6 | 8 | Elena Gemo | 26.86 | ||
| 18 | 4 | 3 | Katerine Savard | 26.87 | ||
| 19 | 6 | 1 | Sviatlana Khakhlova | 26.98 | ||
| 20 | 5 | 2 | Ingvild Snildal | 27.01 | ||
| 21 | 7 | 8 | Ellen Gandy | 27.01 | ||
| 22 | 7 | 2 | Jiao Liuyang | 27.03 | ||
| 23 | 5 | 1 | Kristel Vourna | 27.15 | ||
| 24 | 6 | 5 | Yolane Kukla | 27.24 | ||
| 25 | 5 | 8 | Fabienne Nadarajah | 27.27 | ||
| 26 | 4 | 4 | Hannah Wilson | 27.38 | ||
| 27 | 4 | 5 | Eszter Dara | 27.53 | ||
| 28 | 4 | 6 | Svetlana Fedulova | 27.61 | ||
| 29 | 3 | 5 | Katarina Listopadova | 27.62 | ||
| 30 | 4 | 1 | Sara Oliveira | 27.75 | ||
| 31 | 4 | 8 | Iris Rosenberger | 27.82 | ||
| 32 | 3 | 4 | Jeserick Pinto | 27.91 | ||
| 33 | 3 | 3 | Gabriela Nikitina | 27.92 | ||
| 34 | 4 | 7 | Alana Dillette | 27.98 | ||
| 35 | 3 | 2 | Talita Baqlah | 29.16 | ||
| 36 | 3 | 6 | Dorian McMenemy | 29.37 | ||
| 37 | 3 | 1 | Dalia Torrez | 29.67 | ||
| 38 | 3 | 7 | Kiran Khan | 30.50 | ||
| 39 | 1 | 6 | Ann-Marie Hepler | 30.69 | ||
| 40 | 2 | 3 | Sylvia Brunlehner | 30.81 | ||
| 41 | 2 | 4 | Hazboun Sabine | 31.12 | ||
| 42 | 3 | 8 | Reshika Udugampola | 31.15 | ||
| 43 | 2 | 5 | Judith Meauri | 31.56 | ||
| 44 | 2 | 2 | Kuheilani Snow | 32.27 | ||
| 45 | 2 | 6 | Johanna Umurungi | 32.68 | ||
| 46 | 2 | 7 | Ouyngerel Gantumur | 33.48 | ||
| 47 | 2 | 8 | Deandra van der Colff | 34.06 | ||
| 48 | 2 | 1 | Mariana Henriques | 34.59 | ||
| 49 | 1 | 4 | Karin O'Reilly Clashing | 36.87 | ||
| 50 | 1 | 5 | Shajan Aminath | 38.37 | ||
| 51 | 1 | 3 | Adzo Rebecca Kpossi | 55.17 | ||
| – | 4 | 2 | Hayley Palmer | DNS |
Semifinals
The semifinals were held at 18:19.Semifinal 1
Semifinal 2
Final
The final was held at 18:02.| Rank | Lane | Name | Nationality | Time | Notes |
| 5 | Inge Dekker | 25.71 | |||
| 4 | Therese Alshammar | 25.76 | |||
| 1 | Mélanie Henique | 25.86 | NR | ||
| 4 | 3 | Lu Ying | 25.87 | ||
| 4 | 6 | Sarah Sjöström | 25.87 | ||
| 6 | 2 | Yuka Kato | 26.02 | NR | |
| 7 | 8 | Dana Vollmer | 26.06 | ||
| 8 | 7 | Marieke Guehrer | 26.21 |