The men's javelin throw event at the 2000 World Junior Championships in Athletics was held in Santiago, Chile, at Estadio Nacional Julio Martínez Prádanos on 21 and 22 October.
| Gold | Hardus Pienaar | |
| Silver | Andreas Thorkildsen | |
| Bronze | Park Jae-Myeong |
22 October
| Rank | Name | Nationality | Attempts | Result | Notes | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 2 | 3 | 4 | 5 | 6 | ||||||||
| align=left | align=left | 67.55 | 75.12 | 78.11 | 68.62 | 71.91 | 75.26 | 78.11 | |||||
| align=left | align=left | | 70.60 | 74.72 | 76.34 | 75.21 | 71.37 | 73.97 | 76.34 | ||||
| align=left | align=left | | 71.31 | 69.17 | 71.61 | 72.36 | 71.57 | x | 72.36 | ||||
| 4 | align=left | align=left | 70.89 | x | 64.04 | x | x | 71.93 | 71.93 | ||||
| 5 | align=left | align=left | | 70.08 | 71.20 | x | x | 69.54 | x | 71.20 | |||
| 6 | align=left | align=left |  | 69.03 | 64.41 | 69.21 | 71.02 | 70.81 | x | 71.02 | |||
| 7 | align=left | align=left | 62.15 | 68.39 | 62.12 | 61.91 | x | x | 68.39 | ||||
| 8 | align=left | align=left | 67.51 | 68.14 | x | 65.89 | x | 65.89 | 68.14 | ||||
| 9 | align=left | align=left | 65.68 | 64.21 | x | 65.68 | |||||||
| 10 | align=left | align=left |  | x | 65.63 | x | 65.63 | ||||||
| 11 | align=left | align=left |  | 62.54 | x | 65.55 | 65.55 | ||||||
| 12 | align=left | align=left |  | 64.29 | x | x | 64.29 | ||||||
21 October
| Rank | Name | Nationality | Attempts | Result | Notes | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 2 | 3 | ||||||||
| 1 | align=left | align=left | 75.61 | - | - | 75.61 | Q | |||
| 2 | align=left | align=left | | 70.53 | 61.75 | 69.60 | 70.53 | q | ||
| 3 | align=left | align=left | | 69.27 | 70.11 | 69.72 | 70.11 | q | ||
| 4 | align=left | align=left | | 68.34 | 65.66 | 66.22 | 68.34 | q | ||
| 5 | align=left | align=left | 68.16 | 68.08 | 65.90 | 68.16 | q | |||
| 6 | align=left | align=left | | 67.75 | 65.81 | 66.25 | 67.75 | q | ||
| 7 | align=left | align=left | 67.21 | x | 59.31 | 67.21 | ||||
| 8 | align=left | align=left | 61.53 | 61.99 | 66.32 | 66.32 | ||||
| 9 | align=left | align=left | x | 60.02 | 65.80 | 65.80 | ||||
| 10 | align=left | align=left | 62.46 | 65.76 | 63.67 | 65.76 | ||||
| 11 | align=left | align=left |  | 61.48 | x | 65.67 | 65.67 | |||
| 12 | align=left | align=left |  | 64.78 | 63.90 | x | 64.78 | |||
| 13 | align=left | align=left |  | 63.17 | 63.78 | 64.72 | 64.72 | |||
| 14 | align=left | align=left |  | 59.01 | 60.87 | 60.90 | 60.90 | |||
| 15 | align=left | align=left |  | 60.56 | 60.79 | 59.46 | 60.79 | |||
| 16 | align=left | align=left |  | x | 59.18 | 58.34 | 59.18 | |||
| Rank | Name | Nationality | Attempts | Result | Notes | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 2 | 3 | ||||||||
| 1 | align=left | align=left | 75.04 | - | - | 75.04 | Q | |||
| 2 | align=left | align=left | | 71.51 | 74.20 | - | 74.20 | Q | ||
| 3 | align=left | align=left | | 57.39 | 68.64 | 71.26 | 71.26 | q | ||
| 4 | align=left | align=left | 69.58 | 67.28 | 67.77 | 69.58 | q | |||
| 5 | align=left | align=left | | 66.61 | 68.58 | x | 68.58 | q | ||
| 6 | align=left | align=left | 68.47 | 64.71 | 66.61 | 68.47 | q | |||
| 7 | align=left | align=left |  | x | 67.65 | 66.54 | 67.65 | |||
| 8 | align=left | align=left | | 64.91 | 67.42 | 66.63 | 67.42 | |||
| 9 | align=left | align=left | | 66.59 | 62.73 | 61.72 | 66.59 | |||
| 10 | align=left | align=left | | 65.91 | 60.82 | 63.22 | 65.91 | |||
| 11 | align=left | align=left | 65.58 | 65.16 | 64.46 | 65.58 | ||||
| 12 | align=left | align=left |  | 64.15 | 64.40 | 64.84 | 64.84 | |||
| 13 | align=left | align=left |  | x | 64.57 | x | 64.57 | |||
| 14 | align=left | align=left |  | 63.55 | 62.81 | 61.95 | 63.55 | |||
| 15 | align=left | align=left |  | 61.00 | 62.04 | 63.31 | 63.31 | |||
| 16 | align=left | align=left | | 60.00 | 58.74 | 58.11 | 60.00 | |||
| 17 | align=left | align=left | 56.39 | 57.52 | 52.94 | 57.52 | ||||
According to an unofficial count, 33 athletes from 25 countries participated in the event.