| POS | Rank | Heat | BIB | ATHLETE | COUNTRY | RESULTS | ms* |
|---|---|---|---|---|---|---|---|
| 1 | 1 | 1 | USA | United States |
USA |
42.51 Q WL | |
| 2 | 1 | 3 | GER | Germany |
GER |
43.03 Q SB | |
| 3 | 2 | 1 | BRA | Brazil |
BRA |
43.07 Q SB | |
| 4 | 2 | 3 | JAM | Jamaica |
JAM |
43.08 Q SB | |
| 5 | 3 | 3 | AUS | Australia |
AUS |
43.19 q SB | |
| 6 | 4 | 3 | ITA | Italy |
ITA |
43.40 q SB | |
| 7 | 5 | 3 | KAZ | Kazakhstan |
KAZ |
43.71 | |
| 8 | 1 | 2 | DEN | Denmark |
DEN |
43.90 Q NR | |
| 9 | 6 | 3 | IRL | Ireland |
IRL |
44.02 SB | |
| 10 | 2 | 2 | GHA | Ghana |
GHA |
44.12 Q SB | |
| 11 | 3 | 2 | THA | Thailand |
THA |
44.24 | .234 |
| 12 | 3 | 1 | JPN | Japan |
JPN |
44.24 SB | .238 |
| 13 | 4 | 1 | UKR | Ukraine |
UKR |
44.55 SB | |
| 14 | 7 | 3 | CZE | Czech Republic |
CZE |
44.67 SB | |
| 15 | 8 | 3 | ECU | Ecuador |
ECU |
44.74 SB | |
| 16 | 4 | 2 | NGR | Nigeria |
NGR |
45.07 SB | |
| 1 | TTO | Trinidad and Tobago |
TTO |
DQ | |||
| 1 | CHN | PR of China |
CHN |
DQ | |||
| 2 | CAN | Canada |
CAN |
DQ | |||
| 1 | POL | Poland |
POL |
DNF | |||
| 1 | RSA | South Africa |
RSA |
DNF | |||
| 2 | FRA | France |
FRA |
DNF | |||
| 2 | GBR | Great Britain & NI |
GBR |
DNF |
ms - Milliseconds - shown when two or more competitors finish with the same time down to hundredths of a second