The Women's 50m Breaststroke event at the 10th FINA World Aquatics Championships swam on 26–27 July 2003 in Barcelona, Spain.

Preliminary[1] heats swam during the morning session on July 26, with the top-16 finishers advancing to Semifinals[2] that evening.

The top-8 finishers then advanced to swim again in the Final the next evening.

[3] At the start of the event, the World (WR) and Championship (CR) records were: