The women's 50 metre butterfly event at the 2005 World Aquatics Championships took place between 29 July – 30 July. The heats and semifinals were held on 29 July. The final was held on 30 July.

Records

Prior to the competition, the existing world and championship records were as follows.

	Name	Nationality	Time	Location	Date
World record	Anna-Karin Kammerling Anna-Karin Kammerling Anna-Karin Kammerling is a world-record breaking Swedish swimmer, who was born in Malmö, Sweden. Currently she resides in Sundsvall and trains with the Sundsvalls Swim Club under coach Hans Bergquist....	Sweden Sweden Sweden , officially the Kingdom of Sweden , is a Nordic country on the Scandinavian Peninsula in Northern Europe. Sweden borders with Norway and Finland and is connected to Denmark by a bridge-tunnel across the Öresund....	25.57	Berlin Berlin Berlin is the capital city of Germany and is one of the 16 states of Germany. With a population of 3.45 million people, Berlin is Germany's largest city. It is the second most populous city proper and the seventh most populous urban area in the European Union...	30 July 2002
Championship record	Inge de Bruijn Inge de Bruijn Inge de Bruijn is a Dutch former swimmer. She was a four-time Olympic champion and a former world record holder.-Biography:De Bruijn was born in Barendrecht, South Holland, and tried several sports before settling with swimming....	Netherlands Netherlands The Netherlands is a constituent country of the Kingdom of the Netherlands, located mainly in North-West Europe and with several islands in the Caribbean. Mainland Netherlands borders the North Sea to the north and west, Belgium to the south, and Germany to the east, and shares maritime borders...	23.43	Barcelona Barcelona Barcelona is the second largest city in Spain after Madrid, and the capital of Catalonia, with a population of 1,621,537 within its administrative limits on a land area of...	26 July 2003

No new world or competition records were set during this competition.

Final

Rank	Name	Nationality	Time	Notes
	Danni Miatke Danni Miatke -Biography:Born in Darwin, Northern Territory in 1987, Miatke began competitive swimming in 1995. She first represented the Northern Territory in 1998 at the national School Sport Swimming and Diving Championships. She first won gold for the Territory in 1999 at the Australian Age Championships, in...		26.11
	Anna-Karin Kammerling Anna-Karin Kammerling Anna-Karin Kammerling is a world-record breaking Swedish swimmer, who was born in Malmö, Sweden. Currently she resides in Sundsvall and trains with the Sundsvalls Swim Club under coach Hans Bergquist....		26.36
	Therese Alshammar Therese Alshammar Malin Therese Alshammar is a Swedish swimmer who has won three Olympic medals, 25 World Championship medals, and 43 European Championship medals. Standing at 1.80 m, she is a specialist of short races in freestyle and butterfly...		26.39
4	Fabienne Nadarajah		26.50
5	Antje Buschschulte Antje Buschschulte Antje Buschschulte is a German swimmer. Her best disciplines are the short distance freestyle and backstroke races. Buschschulte swims for the sporting club SC Magdeburg. Up to now, she has won 24 German championships....		26.55
6	Natalie Coughlin Natalie Coughlin Natalie Anne Coughlin is an American swimmer and eleven-time Olympic medallist.At the 2008 Summer Olympics, Coughlin became the first American female athlete in modern Olympic history to win six medals in one Olympics and the first woman ever to win a 100 m backstroke gold in two consecutive...		26.63
6	Inge Dekker Inge Dekker Inge Dekker is a butterfly and freestyle swimmer from Netherlands, who won the bronze medal with the Dutch women's 4×100 m freestyle relay team at the 2004 Summer Olympics in Athens, Greece. She did so alongside Inge de Bruijn, Marleen Veldhuis and Chantal Groot...		26.93
8	Elizabeth Coster		27.23