# 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 | Sweden | 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 | Sweden | 25.68 | Q |
| 2 | 7 | 5 | Jeanette Ottesen | Denmark | 25.88 | Q |
| 3 | 7 | 7 | Dana Vollmer | United States | 25.98 | Q |
| 4 | 6 | 6 | Lu Ying | China | 26.16 | Q |
| 5 | 5 | 4 | Sarah Sjöström | Sweden | 26.17 | Q |
| 6 | 6 | 2 | Christine Magnuson | United States | 26.20 | Q |
| 7 | 6 | 4 | Inge Dekker | Netherlands | 26.32 | Q |
| 8 | 5 | 3 | Mélanie Henique | France | 26.37 | Q |
| 9 | 6 | 3 | Yuka Kato | Japan | 26.37 | Q |
| 10 | 5 | 6 | Triin Aljand | Estonia | 26.43 | Q |
| 11 | 7 | 6 | Tao Li | Singapore | 26.43 | Q |
| 12 | 7 | 3 | Marleen Veldhuis | Netherlands | 26.50 | Q |
| 13 | 5 | 5 | Marieke Guehrer | Australia | 26.59 | Q |
| 14 | 5 | 7 | Daynara de Paula | Brazil | 26.60 | Q |
| 15 | 7 | 1 | Vanessa Mohr | South Africa | 26.69 | Q |
| 16 | 6 | 7 | Amit Ivry | Israel | 26.83 | Q |
| 17 | 6 | 8 | Elena Gemo | Italy | 26.86 | |
| 18 | 4 | 3 | Katerine Savard | Canada | 26.87 | |
| 19 | 6 | 1 | Sviatlana Khakhlova | Belarus | 26.98 | |
| 20 | 5 | 2 | Ingvild Snildal | Norway | 27.01 | |
| 21 | 7 | 8 | Ellen Gandy | Great Britain | 27.01 | |
| 22 | 7 | 2 | Jiao Liuyang | China | 27.03 | |
| 23 | 5 | 1 | Kristel Vourna | Greece | 27.15 | |
| 24 | 6 | 5 | Yolane Kukla | Australia | 27.24 | |
| 25 | 5 | 8 | Fabienne Nadarajah | Austria | 27.27 | |
| 26 | 4 | 4 | Hannah Wilson | Hong Kong | 27.38 | |
| 27 | 4 | 5 | Eszter Dara | Hungary | 27.53 | |
| 28 | 4 | 6 | Svetlana Fedulova | Russia | 27.61 | |
| 29 | 3 | 5 | Katarina Listopadova | Slovakia | 27.62 | |
| 30 | 4 | 1 | Sara Oliveira | Portugal | 27.75 | |
| 31 | 4 | 8 | Iris Rosenberger | Turkey | 27.82 | |
| 32 | 3 | 4 | Jeserick Pinto | Venezuela | 27.91 | |
| 33 | 3 | 3 | Gabriela Ņikitina | Latvia | 27.92 | |
| 34 | 4 | 7 | Alana Dillette | Bahamas | 27.98 | |
| 35 | 3 | 2 | Talita Baqlah | Jordan | 29.16 | |
| 36 | 3 | 6 | Dorian McMenemy | Dominican Republic | 29.37 | |
| 37 | 3 | 1 | Dalia Torrez | Nicaragua | 29.67 | |
| 38 | 3 | 7 | Kiran Khan | Pakistan | 30.50 | |
| 39 | 1 | 6 | Ann-Marie Hepler | Marshall Islands | 30.69 | |
| 40 | 2 | 3 | Sylvia Brunlehner | Kenya | 30.81 | |
| 41 | 2 | 4 | Hazboun Sabine | Palestine | 31.12 | |
| 42 | 3 | 8 | Reshika Udugampola | Sri Lanka | 31.15 | |
| 43 | 2 | 5 | Judith Meauri | Papua New Guinea | 31.56 | |
| 44 | 2 | 2 | Kuheilani Snow | French Polynesia | 32.27 | |
| 45 | 2 | 6 | Johanna Umurungi | Rwanda | 32.68 | |
| 46 | 2 | 7 | Ouyngerel Gantumur | Mongolia | 33.48 | |
| 47 | 2 | 8 | Deandra van der Colff | Botswana | 34.06 | |
| 48 | 2 | 1 | Mariana Henriques | Angola | 34.59 | |
| 49 | 1 | 4 | Karin O'Reilly Clashing | Antigua and Barbuda | 36.87 | |
| 50 | 1 | 5 | Shajan Aminath | Maldives | 38.37 | |
| 51 | 1 | 3 | Adzo Rebecca Kpossi | Togo | 55.17 | |
| - | 4 | 2 | Hayley Palmer | New Zealand | | DNS |

### Semifinals

The semifinals were held at 18:19.

#### Semifinal 1

| Rank | Lane | Name | Nationality | Time | Notes |
| 1 | 5 | Lu Ying | China | 25.87 | Q |
| 2 | 6 | Mélanie Henique | France | 26.29 | Q |
| 3 | 1 | Daynara de Paula | Brazil | 26.39 | |
| 4 | 3 | Christine Magnuson | United States | 26.43 | |
| 5 | 2 | Triin Aljand | Estonia | 26.48 | |
| 6 | 4 | Jeanette Ottesen | Denmark | 26.53 | |
| 7 | 7 | Marleen Veldhuis | Netherlands | 26.61 | |
| 8 | 8 | Amit Ivry | Israel | 26.79 | |

#### Semifinal 2

| Rank | Lane | Name | Nationality | Time | Notes |
| 1 | 4 | Therese Alshammar | Sweden | 25.52 | Q |
| 2 | 6 | Inge Dekker | Netherlands | 25.78 | Q |
| 3 | 3 | Sarah Sjöström | Sweden | 25.90 | Q |
| 4 | 2 | Yuka Kato | Japan | 26.07 | Q, =NR |
| 5 | 1 | Marieke Guehrer | Australia | 26.12 | Q |
| 6 | 5 | Dana Vollmer | United States | 26.32 | Q |
| 7 | 7 | Tao Li | Singapore | 26.34 | |
| 8 | 8 | Vanessa Mohr | South Africa | 26.74 | |

### Final

The final was held at 18:02.
| Rank | Lane | Name | Nationality | Time | Notes |
| | 5 | Inge Dekker | Netherlands | 25.71 | |
| | 4 | Therese Alshammar | Sweden | 25.76 | |
| | 1 | Mélanie Henique | France | 25.86 | NR |
| 4 | 3 | Lu Ying | China | 25.87 | |
| 4 | 6 | Sarah Sjöström | Sweden | 25.87 | |
| 6 | 2 | Yuka Kato | Japan | 26.02 | NR |
| 7 | 8 | Dana Vollmer | United States | 26.06 | |
| 8 | 7 | Marieke Guehrer | Australia | 26.21 | |