The men's 400 metres hurdles event at the 2008 African Championships in Athletics was held at the Addis Ababa Stadium on May 1–May 2.
| width=200 bgcolor=gold | Gold | width=200 bgcolor=silver | Silver | width=200 bgcolor=CC9966 | Bronze |
| L.J. van Zyl | Abderahmane Hamadi | Ibrahim Maïga |
Qualification: First 2 of each heat (Q) and the next 2 fastest (q) qualified for the final.
| Rank | Heat | Name | Nationality | Time | Notes | |
|---|---|---|---|---|---|---|
| 1 | 3 | 50.06 | Q | |||
| 2 | 2 | 50.53 | Q | |||
| 3 | 2 | 50.66 | Q | |||
| 4 | 2 | 50.87 | q | |||
| 5 | 3 | 51.42 | Q | |||
| 6 | 2 | 51.70 | q | |||
| 7 | 1 | 51.87 | Q | |||
| 8 | 1 | 51.93 | Q | |||
| 9 | 3 | 52.35 | ||||
| 10 | 1 | 52.56 | ||||
| 11 | 3 | 53.29 | ||||
| 12 | 3 | 53.30 | ||||
| 13 | 1 | 53.84 | ||||
| 14 | 1 | 53.84 | ||||
| 15 | 3 | 54.08 | ||||
| 16 | 2 | 55.37 | ||||
| 17 | 1 | 55.41 | ||||
| 18 | 3 | 57.01 | ||||
| 19 | 2 | 57.18 | ||||
| 20 | 1 | 58.10 | ||||
| 2 |
| Rank | Lane | Name | Nationality | Time | Notes | |
|---|---|---|---|---|---|---|
| 6 | 48.91 | |||||
| 5 | 49.84 | NR | ||||
| 8 | 49.84 | |||||
| 4 | 4 | 49.93 | ||||
| 5 | 3 | 50.57 | ||||
| 6 | 1 | 51.03 | ||||
| 7 | 2 | 51.83 | ||||
| 8 | 7 | 52.68 |