Swimming at the 2018 European Aquatics Championships – Men's 100 metre butterfly
The Men's 100 metre butterfly competition of the 2018 European Aquatics Championships was held on 8 and 9 August 2018.Records
Prior to the competition, the existing world and championship records were as follows.
| Name | Nation | Time | Location | Date |
| World record | Michael Phelps | | 49.82 | Rome | 1 August 2009 |
| European record | Milorad Čavić | | 49.95 | Rome | 1 Aug 2009 |
| Championship record | László Cseh | | 50.86 | London | 21 May 2016 |
The following new records were set during this competition.
Results
Heats
The heats were started on 8 August at 09:35.Semifinals
The semifinals were started on 8 August at 17:17.Semifinal 1
Semifinal 2
Final
The final was started on 9 August at 17:00.
| Rank | Lane | Name | Nationality | Time | Notes |
| 8 | Piero Codia | | 50.64 | CR |
| 1 | Mehdy Metella | | 51.24 | |
| 2 | James Guy | | 51.42 | |
| 4 | 6 | Kristóf Milák | | 51.51 | |
| 5 | 7 | Egor Kuimov | | 51.65 | |
| 6 | 3 | Konrad Czerniak | | 51.72 | |
| 7 | 5 | Aleksandr Sadovnikov | | 51.81 | |
| 8 | 4 | László Cseh | | 51.84 | |
