Swimming at the 2005 World Aquatics Championships – Women's 100 metre breaststroke
The Women's 100 Breaststroke event at the 11th FINA World Aquatics Championships swam 25+26 July 2005 in Montreal, Canada. Preliminary and semifinal heats were swum on 25 July, with the prelims in the morning session and the semis in the evening. The final went the next evening.
At the start of the event, the existing world and championship records were:
Prelims
Semifinals
Final
| Place | Swimmer | Nation | Time | Notes |
| 1 | Leisel Jones | Australia | 1:06.25 | |
| 2 | Jessica Hardy | USA | 1:06.62 | |
| 3 | Tara Kirk | USA | 1:07.43 | |
| 4 | LUO Xuejuan | China | 1:07.60 | |
| 5 | Brooke Hanson | Australia | 1:08.07 | |
| 6 | Suzaan van Biljon | South Africa | 1:08.38 | |
| 7 | Sarah Poewe | Germany | 1:08.47 | |
| 8 | Chiara Boggiatto | Italy | 1:08.98 | |
