Semifinal 1
Saturday, July 29, 2017, 06:45pm GMT – 06:45pm GMT
| Name | Team | Times | |
|---|---|---|---|
| 1 |  Camille Lacourt | France | 24.3″ |
| 2 |  Matt Grevers | United States | + 0.35″ |
| 3 | Pavel Sankovich | Belarus | + 0.44″ |
| 4 | Jonatan Kopelev | Israel | + 0.54″ |
| 5 | Grigory Tarasevich | Russia | + 0.56″ |
| 6 |  Guilherme Guido | Brazil | + 0.61″ |
| 7 | Youngjun Won | Korea | + 0.72″ |
| 8 | I Gede Siman Sudartawa | Indonesia | + 0.74″ |