| POS | BIB | ATHLETE | COUNTRY | MARK | Reaction Time | 
|---|---|---|---|---|---|
| 1 | 752 | David Klech |  USA | 50.96 Q WYL | 0.171 | 
| 2 | 427 | Jaber Adel Assiri |  KSA | 51.13 Q PB | 0.153 | 
| 3 | 608 | Wiekus Jonck |  RSA | 51.22 Q PB | 0.235 | 
| 4 | 670 | Salih Dar |  SUD | 51.62 Q PB | 0.165 | 
| 5 | 639 | Viacheslav Sakaev |  RUS | 51.73 PB | 0.203 | 
| 6 | 398 | Robert Kigen |  KEN | 51.89 | 0.177 | 
| 7 | 697 | Ching-Chun Wang |  TPE | 54.02 | 0.157 | 
| 8 | 593 | Abdulraoof Mohammed Mohammed |  QAT | 56.15 | 0.164 | 
| POS | BIB | ATHLETE | COUNTRY | MARK | Reaction Time | 
|---|---|---|---|---|---|
| 1 | 428 | Mohammed Yahya Daak |  KSA | 51.66 Q | 0.186 | 
| 2 | 365 | Romel Lewis |  JAM | 51.92 Q PB | 0.181 | 
| 3 | 748 | Timothy Grier |  USA | 52.13 Q PB | 0.247 | 
| 4 | 583 | Victor Valentin |  PUR | 52.78 | 0.217 | 
| 5 | 204 | Santiago Albero |  ESP | 53.07 PB | 0.154 | 
| 6 | 282 | Christoph Kaesmacher |  GER | 53.17 | 0.167 | 
| 7 | 602 | Pieter Botha |  RSA | 53.25 | 0.181 | 
| 672 | Abdulagadir Idriss |  SUD | DQ | 0.221 |