Semifinal 1
mercredi 9 août 2017, 21h55 GMT – 21h55 GMT
| Nom | Équipe | Temps | |
|---|---|---|---|
| 1 |  Isiah Young | United States | 20.12″ |
| 2 |  Isaac Makwala | Botswana | + 0.02″ |
| 3 |  Nethaneel Mitchell-Blake | Great Britain | + 0.07″ |
| 4 | David Lima | Portugal | + 0.44″ |
| 5 |  Shota Iizuka | Japan | + 0.5″ |
| 6 |  Filippo Tortu | Italy | + 0.5″ |
| 7 |  Akani Simbine | South Africa | + 0.5″ |
| 8 |  Kyle Greaux | Trinidad & Tobago | + 0.53″ |
| 9 |  Rasheed Dwyer | Jamaica | + 0.57″ |