The Men's 100 metre backstroke competition of the 2024 World Aquatics Swimming Championships (25 m) was held on 10 and 11 December 2024.

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

The heats were started on 10 December at 09:54.

[2] The semifinals were started on 10 December at 18:34.

[3] The final was started on 11 December at 17:40.