| POS | Rank | Heat | BIB | ATHLETE | COUNTRY | RESULTS |
|---|---|---|---|---|---|---|
| 1 | 1 | 3 | 1120 | LaShawn Merritt |
USA |
44.31 Q |
| 2 | 1 | 2 | 1151 | Jeremy Wariner |
USA |
44.34 Q |
| 3 | 1 | 1 | 1141 | Angelo Taylor |
USA |
44.45 Q |
| 4 | 2 | 3 | 561 | Leslie Djhone |
FRA |
44.46 Q NR |
| 5 | 3 | 3 | 425 | Tyler Christopher |
CAN |
44.47 q SB |
| 6 | 2 | 2 | 352 | Chris Brown |
BAH |
44.52 Q |
| 7 | 2 | 1 | 1037 | Johan Wissman |
SWE |
44.56 Q NR |
| 8 | 3 | 1 | 351 | Avard Moncur |
BAH |
44.86 q SB |
| 9 | 4 | 3 | 334 | John Steffensen |
AUS |
44.95 |
| 10 | 3 | 2 | 1049 | Ato Stephens |
TTO |
45.12 SB |
| 11 | 4 | 1 | 455 | Nery Brenes |
CRC |
45.14 |
| 12 | 4 | 2 | 451 | Gary Kikaya |
COD |
45.14 |
| 13 | 5 | 2 | 713 | Ricardo Chambers |
JAM |
45.18 |
| 14 | 5 | 1 | 329 | Sean Wroe |
AUS |
45.25 PB |
| 15 | 6 | 2 | 684 | David Gillick |
IRL |
45.37 |
| 16 | 5 | 3 | 349 | Andrae Williams |
BAH |
45.40 |
| 17 | 6 | 1 | 658 | Alleyne Francique |
GRN |
45.41 |
| 18 | 7 | 2 | 380 | California Molefe |
BOT |
45.47 |
| 19 | 7 | 1 | 491 | Arismendy Peguero |
DOM |
45.54 |
| 20 | 8 | 2 | 459 | Williams Collazo |
CUB |
45.54 |
| 21 | 8 | 1 | 708 | Michael Blackwood |
JAM |
45.60 |
| 22 | 6 | 3 | 584 | Timothy Benjamin |
GBR |
46.17 |
| 23 | 7 | 3 | 1168 | Young Talkmore Nyongani |
ZIM |
46.23 |
| 3 | 706 | Sanjay Ayre |
JAM |
DNF |