| POS | BIB | ATHLETE | COUNTRY | MARK | Reaction Time | 
|---|---|---|---|---|---|
| 1 | 1155 | Derrick Williams |  USA | 49.65 Q | 0.183 | 
| 2 | 898 | Marek Plawgo |  POL | 49.66 Q | 0.175 | 
| 3 | 442 | Yan Meng |  CHN | 49.66 Q | 0.174 | 
| 4 | 948 | L.J. van Zyl |  RSA | 49.71 | 0.167 | 
| 5 | 398 | Raphael Fernandes |  BRA | 50.33 | 0.134 | 
| 6 | 660 | Allan Ayala |  GUA | 52.26 | 0.181 | 
| 7 | 666 | Jonnie Lowe |  HON | 52.66 | 0.213 | 
| 570 | Naman Keïta |  FRA | DQ | 0.212 | 
| POS | BIB | ATHLETE | COUNTRY | MARK | Reaction Time | 
|---|---|---|---|---|---|
| 1 | 1091 | James Carter |  USA | 49.52 Q | 0.160 | 
| 2 | 881 | Bayano Kamani |  PAN | 49.67 Q | 0.160 | 
| 3 | 692 | Gianni Carabelli |  ITA | 49.81 Q | 0.163 | 
| 4 | 763 | Yevgeniy Meleshenko |  KAZ | 49.94 Q | 0.160 | 
| 5 | 840 | Kurt Couto |  MOZ | 50.06 | 0.205 | 
| 6 | 761 | Masahira Yoshikata |  JPN | 50.59 | 0.187 | 
| 939 | Alwyn Myburgh |  RSA | DNF | 0.173 | 
| POS | BIB | ATHLETE | COUNTRY | MARK | Reaction Time | 
|---|---|---|---|---|---|
| 1 | 720 | Danny McFarlane |  JAM | 48.91 Q | 0.187 | 
| 2 | 1093 | Kerron Clement |  USA | 49.07 Q | 0.189 | 
| 3 | 914 | Javier Culson |  PUR | 49.09 Q | 0.173 | 
| 4 | 911 | Edivaldo Monteiro |  POR | 49.66 Q | 0.169 | 
| 5 | 952 | Aleksandr Derevyagin |  RUS | 49.66 q | 0.172 | 
| 6 | 756 | Dai Tamesue |  JPN | 49.67 | 0.197 | 
| 7 | 589 | Dale Garland |  GBR | 49.98 | 0.186 | 
| POS | BIB | ATHLETE | COUNTRY | MARK | Reaction Time | 
|---|---|---|---|---|---|
| 1 | 426 | Adam Kunkel |  CAN | 49.03 Q | 0.178 | 
| 2 | 654 | PeriklÃs Iakovákis |  GRE | 49.10 Q | 0.177 | 
| 3 | 934 | Pieter de Villiers |  RSA | 49.24 Q | 0.188 | 
| 4 | 558 | Fadil Bellaabouss |  FRA | 49.51 Q | 0.180 | 
| 5 | 368 | Jonathan Williams |  BIZ | 49.61 q | 0.180 | 
| 6 | 888 | Mowen Boino |  PNG | 52.45 | 0.209 | 
| 710 | Markino Buckley |  JAM | DNF | 0.173 | |
| 1061 | Ali Obaid Shirook |  UAE | DNS | 0.000 | 
| POS | BIB | ATHLETE | COUNTRY | MARK | Reaction Time | 
|---|---|---|---|---|---|
| 1 | 490 | Felix Sánchez |  DOM | 48.70 Q SB | 0.164 | 
| 2 | 1106 | Bershawn Jackson |  USA | 48.87 Q | 0.143 | 
| 3 | 752 | Kenji Narisako |  JPN | 48.92 Q SB | 0.172 | 
| 4 | 722 | Isa Phillips |  JAM | 49.38 Q | 0.234 | 
| 5 | 835 | Ibrahim Maïga |  MLI | 49.55 q | 0.195 | 
| 6 | 675 | Joseph G. Abraham |  IND | 49.64 q | 0.142 | 
| 7 | 520 | José MarÃa Romera |  ESP | 50.82 | 0.155 | 
| 8 | 880 | Haq Nawaz |  PAK | 51.72 PB | 0.216 |