| POS | ATHLETE | COUNTRY | MARK | Reaction Time | 
|---|---|---|---|---|
| 1 | Derrick Adkins |  USA | 48.25 Q | |
| 2 | Stéphane Diagana |  FRA | 48.37 Q | |
| 3 | Ruslan Mashchenko |  RUS | 48.75 Q | |
| 4 | Eronilde Nunes de Araújo |  BRA | 48.85 Q | |
| 5 | Erick Keter |  KEN | 49.53 | |
| 6 | Jose Perez |  CUB | 50.20 | |
| Fabrizio Mori |  ITA | DQ | ||
| Shunji Karube |  JPN | DQ | 
| POS | ATHLETE | COUNTRY | MARK | Reaction Time | 
|---|---|---|---|---|
| 1 | Samuel Matete |  ZAM | 48.50 Q | |
| 2 | Sven Nylander |  SWE | 48.53 Q | |
| 3 | Kazuhiko Yamazaki |  JPN | 48.64 Q | |
| 4 | Ken Harnden |  ZIM | 48.73 Q | |
| 5 | Laurent Ottoz |  ITA | 48.94 | |
| 6 | Octavius Terry |  USA | 49.49 | |
| 7 | Dusán Kovács |  HUN | 49.57 | |
| Winthrop Graham |  JAM | DQ |