Semifinal
mercredi 9 août 2017, 21h55 GMT – 21h55 GMT
| Nom | Équipe | Temps | |
|---|---|---|---|
| 1 |  Isiah Young | United States | 20.12″ |
| 2 |  Jereem Richards | Trinidad & Tobago | + 0.02″ |
| 3 |  Isaac Makwala | Botswana | + 0.02″ |
| 4 |  Ramil Guliyev | Turkey | + 0.05″ |
| 5 |  Nethaneel Mitchell-Blake | Great Britain | + 0.07″ |
| 6 | Ameer Webb | United States | + 0.1″ |
| 7 |  Wayde Van Niekerk | South Africa | + 0.16″ |
| 8 |  Christophe Lemaitre | FFA - France Athlétisme | + 0.18″ |
| 9 | Daniel Talbot | Great Britain | + 0.26″ |
| 10 |  Abdul hakim Sani brown | Japan | + 0.31″ |
| 11 |  Yohan Blake | Jamaica | + 0.4″ |
| 12 | Sydney Siame | Zambia | + 0.42″ |
| 13 | David Lima | Portugal | + 0.44″ |
| 14 | Kyree King | United States | + 0.47″ |
| 15 | Jan Volko | Slovakia | + 0.49″ |
| 16 | Shota Iizuka | Japan | + 0.5″ |
| 17 |  Filippo Tortu | Italy | + 0.5″ |
| 18 |  Akani Simbine | South Africa | + 0.5″ |
| 19 | Kyle Greaux | Trinidad & Tobago | + 0.53″ |
| 20 |  Rasheed Dwyer | Jamaica | + 0.57″ |
| 21 | Likoúrgos-Stéfanos Tsákonas | Greece | + 0.61″ |
| 22 | Winston George | Guyana | + 0.62″ |
| 23 | Wilfried Koffi | Ivory Coast | + 0.68″ |
| 24 |  Zharnel Hughes | Great Britain | + 0.73″ |
| 25 |  Alex Wilson | Switzerland | + 1.1″ |