| POS | BIB | ATHLETE | COUNTRY | MARK | Reaction Time | 
|---|---|---|---|---|---|
| 1 | 643 | Sandie Richards |  JAM | 51.98 Q | 0.213 | 
| 2 | 731 | Olesya Zykina |  RUS | 52.18 Q | 0.253 | 
| 3 | 777 | Monique Hennagan |  USA | 52.43 Q | 0.198 | 
| 4 | 593 | Catherine Murphy |  GBR | 52.45 | 0.162 | 
| 5 | 701 | Ionela Târlea |  ROU | 52.87 | 0.191 | 
| 6 | 537 | Foy Williams |  CAN | 53.61 | 0.163 | 
| POS | BIB | ATHLETE | COUNTRY | MARK | Reaction Time | 
|---|---|---|---|---|---|
| 1 | 713 | Olga Kotlyarova |  RUS | 51.63 Q | 0.246 | 
| 2 | 786 | Suziann Reid |  USA | 51.84 Q SB | 0.145 | 
| 3 | 539 | Kaltouma Nadjina |  CHA | 51.92 Q NR | 0.187 | 
| 4 | 610 | Shanta Ghosh |  GER | 51.93 | 0.179 | 
| 5 | 619 | Aliann Pompey |  GUY | 53.18 | 0.191 | 
| 6 | 521 | Natallia Solohub |  BLR | 53.60 | 0.139 |