The women's 100 metre breaststroke competition of the 2018 FINA World Swimming Championships (25 m) was held on 14 and 15 December 2018.

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

The heats were started on 14 December at 10:49.

[2] The semifinals were started on 14 December at 20:42.

[3] The final was held on 15 December at 20:37.