# Swimming at the 2009 World Aquatics Championships – Women's 50 metre butterfly

The heats for the women's 50 m butterfly race at the 2009 World Championships took place in the morning and evening of 31 July, with the final in the evening session of 1 August at the Foro Italico in Rome, Italy.

## Records

Prior to this competition, the existing world and competition records were as follows:
| World record | Marleen Veldhuis (NED) | 25.33 | Amsterdam, Netherlands | 19 April 2009 |
| Championship record | Therese Alshammar (SWE) | 25.82 | Melbourne, Australia | 30 March 2007 |
The following records were established during the competition:
| Date | Round | Name | Nationality | Time | Record |
| 31 July | Heat 10 | Sarah Sjöström | Sweden | 25.74 | CR |
| 31 July | Heat 13 | Therese Alshammar | Sweden | 25.44 | CR |
| 31 July | Semifinal 1 | Marleen Veldhuis | Netherlands | 25.28 | WR |
| 31 July | Semifinal 2 | Therese Alshammar | Sweden | 25.07 | WR |

## Results
### Heats

| Rank | Name | Nationality | Time | Heat | Lane | Notes |
| 1 | Therese Alshammar | Sweden | 25.44 | 13 | 4 | CR, NR |
| 2 | Marleen Veldhuis | Netherlands | 25.58 | 14 | 4 | |
| 3 | Ingvild Snildal | Norway | 25.62 | 13 | 7 | NR |
| 4 | Sarah Sjöström | Sweden | 25.74 | 10 | 3 | |
| 5 | Marieke Guehrer | Australia | 25.83 | 14 | 5 | |
| 6 | Silvia di Pietro | Italy | 25.84 | 13 | 6 | NR |
| 7 | Jeanette Ottesen | Denmark | 25.86 | 14 | 3 | NR |
| 8 | Yafei Zhou | China | 26.00 | 14 | 2 | AS |
| 9 | Christine Magnuson | United States | 26.06 | 13 | 5 | |
| 10 | Gabriella Silva | Brazil | 26.07 | 13 | 2 | SA |
| 11 | Daynara de Paula | Brazil | 26.11 | 13 | 8 | |
| 12 | Hinkelien Schreuder | Netherlands | 26.21 | 12 | 5 | |
| 12 | Sviatlana Khakhlova | Belarus | 26.21 | 14 | 8 | |
| 14 | Triin Aljand | Estonia | 26.27 | 14 | 9 | |
| 15 | Diane Bui Duyet | France | 26.35 | 14 | 6 | |
| 16 | Daniela Samulski | Germany | 26.36 | 12 | 8 | |
| 17 | Dara Torres | United States | 26.41 | 12 | 4 | |
| 17 | Libby Trickett | Australia | 26.41 | 13 | 3 | |
| 19 | Yuka Kato | Japan | 26.46 | 12 | 1 | |
| 20 | Irina Bespalova | Russia | 26.49 | 12 | 2 | NR |
| 21 | Jiao Liuyang | China | 26.53 | 12 | 3 | |
| 22 | Fabienne Nadarajah | Austria | 26.55 | 14 | 7 | |
| 23 | Amit Ivry | Israel | 26.59 | 12 | 7 | |
| 23 | Iryna Niafedava | Belarus | 26.59 | 13 | 9 | |
| 25 | Eszter Dara | Hungary | 26.68 | 11 | 4 | NR |
| 26 | Jemma Lowe | Great Britain | 26.71 | 11 | 8 | |
| 26 | Mélanie Henique | France | 26.71 | 12 | 6 | |
| 28 | Tao Li | Singapore | 26.76 | 10 | 5 | |
| 29 | Katharina Stiberg | Norway | 26.77 | 12 | 0 | |
| 30 | Micha Kathrine Østergaard Jensen | Denmark | 26.79 | 11 | 3 | |
| 31 | Martina Moravcová | Slovakia | 26.80 | 12 | 9 | |
| 32 | Cristina Maccagnola | Italy | 26.82 | 14 | 1 | |
| 33 | Kimberly Buys | Belgium | 26.85 | 14 | 0 | |
| 34 | Alana Dillette | Bahamas | 27.07 | 13 | 9 | NR |
| 35 | Beatrix Bordas | Hungary | 27.13 | 13 | 1 | |
| 36 | Yui Miyamoto | Japan | 27.16 | 11 | 6 | |
| 37 | Emilia Pikkarainen | Finland | 27.23 | 11 | 5 | |
| 38 | Ellen Gandy | Great Britain | 27.28 | 11 | 2 | |
| 39 | Victoria Poon | Canada | 27.31 | 13 | 0 | |
| 40 | Katarina Listopadova | Slovakia | 27.37 | 10 | 4 | |
| 41 | Jane Trepp | Estonia | 27.39 | 10 | 9 | |
| 42 | Anna Schoholeva | Cyprus | 27.43 | 11 | 0 | |
| 43 | Iris Rosenberger | Turkey | 27.44 | 10 | 8 | |
| 44 | Fella Bennaceur | Algeria | 27.50 | 10 | 6 | NR |
| 45 | Audrey Lacroix | Canada | 27.52 | 9 | 5 | |
| 45 | Kelly Shim Robinson | Hong Kong | 27.52 | 9 | 0 | |
| 47 | Linda Laihorinne | Finland | 27.53 | 9 | 7 | |
| 48 | Carolina Colorado Henao | Colombia | 27.56 | 11 | 7 | |
| 49 | Laetitia Perez | Switzerland | 27.61 | 11 | 1 | |
| 50 | Farida Osman | Egypt | 27.78 | 9 | 3 | |
| 51 | Sofija Djelic | Slovenia | 27.82 | 9 | 2 | |
| 52 | Kristina Tchernychev | Israel | 27.88 | 9 | 6 | |
| 53 | Binta Zahra Diop | Senegal | 27.96 | 9 | 9 | |
| 54 | Rita Medrano | Mexico | 27.97 | 8 | 5 | NR |
| 55 | Marellyn Lammert Liew | Malaysia | 27.98 | 9 | 8 | |
| 56 | Hang Yu Sze | Hong Kong | 28.12 | 9 | 1 | |
| 57 | Aneta Pechancova | Czech Republic | 28.18 | 9 | 4 | |
| 58 | Jeserick Pinto | Venezuela | 28.20 | 10 | 1 | |
| 59 | Klara Vaclavikova | Czech Republic | 28.23 | 7 | 5 | |
| 60 | Sharntelle McLean | Trinidad and Tobago | 28.25 | 8 | 3 | |
| 61 | Christine Mailliet | Luxembourg | 28.36 | 8 | 6 | |
| 62 | Grite Apanaviciute | Lithuania | 28.38 | 10 | 0 | |
| 63 | Mylene Ong | Singapore | 28.48 | 8 | 4 | |
| 64 | Marie Laura Meza | Costa Rica | 28.58 | 7 | 4 | NR |
| 65 | Aiste Dobrovolskaite | Lithuania | 28.62 | 8 | 2 | |
| 65 | Nadia Colovini | Argentina | 28.62 | 10 | 2 | NR |
| 67 | Monica Bernardo | Mozambique | 28.88 | 7 | 3 | |
| 68 | Ramond Sherazad | Morocco | 29.01 | 7 | 1 | NR |
| 69 | Gizem Cam | Turkey | 29.16 | 8 | 7 | |
| 70 | Ma Cheok Mei | Macau | 29.21 | 8 | 8 | |
| 71 | Achieng Ajulu-Bushell | Kenya | 29.32 | 7 | 2 | NR |
| 72 | Nishani Cicilson | Suriname | 29.34 | 6 | 3 | |
| 73 | Dalia Torrez | Nicaragua | 29.35 | 7 | 7 | |
| 74 | Chittaranjan Shubha | India | 29.48 | 7 | 8 | |
| 75 | Veronica Vdovicenco | Moldova | 29.50 | 7 | 6 | |
| 76 | Silvie Ketelaars | Netherlands Antilles | 29.53 | 6 | 6 | |
| 77 | Shaila Millum Garðarnar | Faroe Islands | 29.56 | 6 | 2 | NR |
| 78 | Maria Georgina Gandionco | Philippines | 29.60 | 7 | 1 | |
| 79 | Karen Milenka Torrez Guzman | Bolivia | 29.63 | 6 | 4 | |
| 80 | Razan Taha | Jordan | 29.66 | 8 | 9 | |
| 81 | Kimberley Eeson | Zimbabwe | 29.69 | 5 | 1 | |
| 82 | Laura lucia Paz Chavez | Honduras | 29.72 | 5 | 8 | |
| 83 | Moira Fraser | Zimbabwe | 29.85 | 5 | 6 | |
| 84 | Jonay Briedenhann | Namibia | 29.86 | 6 | 7 | NR |
| 85 | Ileana Murillo | El Salvador | 30.05 | 8 | 1 | |
| 86 | Marianela Quesada | Costa Rica | 30.12 | 5 | 0 | |
| 87 | Karrakchou Lilia | Morocco | 30.13 | 4 | 5 | |
| 88 | Kendese Nangle | Jamaica | 30.18 | 6 | 5 | |
| 89 | Davina Mangion | Malta | 30.24 | 6 | 9 | |
| 90 | Kathryn Millin | Eswatini | 30.29 | 3 | 2 | |
| 91 | Nilshaira Isenia | Netherlands Antilles | 30.33 | 5 | 2 | |
| 92 | Long Chi Wun | Macau | 30.47 | 7 | 0 | |
| 93 | Karla Toscano | Guatemala | 30.50 | 4 | 5 | |
| 94 | Ashley Bransford | Aruba | 30.53 | 5 | 7 | |
| 95 | Labake Anthonia Oriretan | Nigeria | 30.63 | 3 | 7 | |
| 96 | Vandita Dhariyal | India | 30.65 | 3 | 6 | |
| 96 | Amina Meho | Lebanon | 30.65 | 6 | 1 | |
| 98 | Selma Atic | Bosnia and Herzegovina | 30.74 | 8 | 0 | |
| 99 | Sharon Paola Fajardo Sierra | Honduras | 30.79 | 5 | 5 | |
| 100 | Li Chuen Cheong Estelle | Mauritius | 30.97 | 4 | 4 | |
| 101 | Graciela Peinado Ibanez | Bolivia | 31.05 | 2 | 2 | |
| 102 | Talisa Pace | Malta | 31.06 | 6 | 0 | |
| 103 | Stephanie Rasoamanana | Madagascar | 31.30 | 3 | 4 | |
| 104 | Gessica Stagno | Mozambique | 31.33 | 3 | 8 | |
| 105 | Pina Ercolano | Kenya | 31.35 | 4 | 6 | |
| 105 | Adele Rova | Fiji | 31.35 | 4 | 0 | |
| 107 | Sara Abdullahu | Albania | 31.41 | 4 | 9 | |
| 108 | Estellah Fils Rabetsara | Madagascar | 31.45 | 4 | 2 | |
| 109 | Noelyn Faussane | French Polynesia | 31.69 | 3 | 0 | |
| 110 | Cheyenne Rova | Fiji | 31.79 | 4 | 1 | |
| 111 | Tin Hon Ko Adeline Mei-Li | Mauritius | 31.80 | 4 | 3 | |
| 112 | Shannon Austin | Seychelles | 31.92 | 2 | 2 | |
| 113 | Miniruwani Samarakoon | Sri Lanka | 32.14 | 3 | 1 | |
| 114 | Danielle Bernadine Findlay | Zambia | 32.17 | 3 | 3 | |
| 115 | Ruth Carvalho | Angola | 32.20 | 2 | 5 | |
| 115 | Julia Alves | Marshall Islands | 32.20 | 2 | 7 | |
| 117 | Noelle Anyika Smith | Seychelles | 32.34 | 2 | 8 | |
| 118 | Sabine Hazboun | Palestine | 32.39 | 2 | 4 | |
| 119 | Maria Grace Koh | Brunei | 32.59 | 4 | 8 | |
| 120 | Amnahliyani Mohamad Husain | Brunei | 32.65 | 2 | 1 | |
| 121 | Judith Ilan Meauri | Papua New Guinea | 32.82 | 3 | 9 | |
| 122 | Debra Daniel | Federated States of Micronesia | 32.83 | 2 | 6 | |
| 123 | Debora Keci | Albania | 32.92 | 3 | 5 | |
| 124 | Kiran Khan | Pakistan | 33.13 | 5 | 3 | |
| 125 | Yara Dowani | Palestine | 33.64 | 6 | 8 | |
| 126 | Sausan Aishath | Maldives | 33.76 | 1 | 5 | |
| 127 | Mariam Foum | Tanzania | 34.67 | 1 | 3 | |
| 128 | Julianne Kirchner | Marshall Islands | 34.96 | 1 | 2 | |
| 129 | Katerina Izmailova | Tajikistan | 36.63 | 5 | 4 | |
| 130 | Rida Mitha | Pakistan | 37.54 | 2 | 9 | |
| 131 | Uwamahoro Elsie | Burundi | 43.87 | 2 | 0 | |
| 132 | Awa Keita | Mali | 44.33 | 1 | 6 | |
| – | Ana Euceda Gutierrez | Honduras | DNS | 5 | 9 | |
| – | Gantumur Oyungerel | Mongolia | DSQ | 1 | 4 | |
| – | Loren Yamile Bahamonde | Ecuador | DSQ | 11 | 9 | |

### Semifinals

| Rank | Name | Nationality | Time | Heat | Lane | Notes |
| 1 | Therese Alshammar | Sweden | 25.07 | 2 | 4 | WR |
| 2 | Marleen Veldhuis | Netherlands | 25.28 | 1 | 4 | NR |
| 3 | Ingvild Snildal | Norway | 25.53 | 2 | 5 | NR |
| 4 | Marieke Guehrer | Australia | 25.58 | 2 | 3 | OC |
| 5 | Yafei Zhou | China | 25.59 | 1 | 6 | AS |
| 6 | Sarah Sjöström | Sweden | 25.76 | 1 | 5 | |
| 7 | Daynara de Paula | Brazil | 25.85 | 2 | 7 | SA |
| 8 | Diane Bui Duyet | France | 25.87 | 2 | 8 | NR |
| 9 | Jeanette Ottesen | Denmark | 25.90 | 2 | 6 | |
| 10 | Hinkelien Schreuder | Netherlands | 25.94 | 1 | 7 | |
| 11 | Silvia di Pietro | Italy | 26.00 | 1 | 3 | |
| 12 | Sviatlana Khakhlova | Belarus | 26.00 | 2 | 1 | |
| 13 | Gabriella Silva | Brazil | 26.02 | 1 | 2 | |
| 14 | Triin Aljand | Estonia | 26.16 | 1 | 1 | |
| 15 | Christine Magnuson | United States | 26.21 | 2 | 2 | |
| 16 | Daniela Samulski | Germany | 26.33 | 1 | 8 | NR |

### Final

| Rank | Name | Nationality | Time | Lane | Notes |
| | Marieke Guehrer | Australia | 25.48 | 6 | OC |
| | Yafei Zhou | China | 25.57 | 2 | AS |
| | Ingvild Snildal | Norway | 25.58 | 3 | |
| 4 | Therese Alshammar | Sweden | 25.59 | 4 | |
| 5 | Marleen Veldhuis | Netherlands | 25.63 | 5 | |
| 6 | Sarah Sjöström | Sweden | 25.66 | 7 | |
| 7 | Diane Bui Duyet | France | 25.92 | 8 | |
| 8 | Daynara de Paula | Brazil | 26.12 | 1 | |