Semifinal 2
lundi 7 août 2017, 21h55 GMT – 21h55 GMT
| Nom | Équipe | Temps | |
|---|---|---|---|
| 1 |  Salwa Eid Naser | Bahrain | 50.08″ |
| 2 |  Allyson Felix | United States | + 0.04″ |
| 3 |  Novlene Williams-Mills | Jamaica | + 0.59″ |
| 4 |  Shericka Jackson | Jamaica | + 0.62″ |
| 5 | Lydia Mashila | Botswana | + 1.49″ |
| 6 | Yinka Ajayi | Nigeria | + 2.02″ |
| 7 | Nirmala Sheoran | India | + 2.99″ |
| 8 |  Irini Vasiliou | Greece | + 3.19″ |