The Men's 100 metre backstroke competition of the 2020 European Aquatics Championships was held on 19 and 20 May 2021.

[1][2] Prior to the competition, the existing world, European and championship records were as follows.

The heats were started on 19 May at 10:30.

[3] The semifinals were held on 19 May at 18:30.

[4] The final was held on 20 May at 18:06.