The men's 20 kilometres road run event at the 1990 World Junior Championships in Athletics was held in Plovdiv, Bulgaria, on 12 August.[1]
| Gold | Cosmas Ndeti | |
| Silver | Juma Ninga | |
| Bronze | Dagne Debela |
12 August
| Rank | Name | Nationality | Time | Notes | |||
|---|---|---|---|---|---|---|---|
| align=left | align=left | | 59:42 | ||||
| align=left | align=left | 1:00:30 | |||||
| align=left | align=left | | 1:01:02 | ||||
| 4 | align=left | align=left | | 1:02:52 | |||
| 5 | align=left | align=left |  | 1:03:01 | |||
| 6 | align=left | align=left |  | 1:03:09 | |||
| 7 | align=left | align=left | 1:03:37 | ||||
| 8 | align=left | align=left | 1:03:42 | ||||
| 9 | align=left | align=left | 1:03:49 | ||||
| 10 | align=left | align=left | 1:04:10 | ||||
| 11 | align=left | align=left |  | 1:04:25 | |||
| 12 | align=left | align=left |  | 1:04:29 | |||
| 13 | align=left | align=left |  | 1:04:54 | |||
| 14 | align=left | align=left | 1:05:10 | ||||
| 15 | align=left | align=left | 1:05:28 | ||||
| 16 | align=left | align=left | | 1:05:53 | |||
| 17 | align=left | align=left |  | 1:06:02 | |||
| 18 | align=left | align=left |  | 1:06:19 | |||
| 19 | align=left | align=left | 1:06:35 | ||||
| 20 | align=left | align=left |  | 1:06:43 | |||
| 21 | align=left | align=left | | 1:07:32 | |||
| 22 | align=left | align=left | | 1:07:57 | |||
| 23 | align=left | align=left | | 1:08:00 | |||
| 24 | align=left | align=left |  | 1:08:26 | |||
| 25 | align=left | align=left | | 1:10:02 | |||
| 26 | align=left | align=left |  | 1:11:45 | |||
| 27 | align=left | align=left |  | 1:12:27 | |||
| align=left | align=left | DNF |
According to an unofficial count, 28 athletes from 20 countries participated in the event.