The men's hammer throw event at the 2004 World Junior Championships in Athletics was held in Grosseto, Italy, at Stadio Olimpico Carlo Zecchini on 15 and 16 July. A 6 kg (junior implement) hammer was used.
| Gold | Andrey Azarenkov | |
| Silver | Mohsen Anany | |
| Bronze | Kamilius Bethke |
16 July
| Rank | Name | Nationality | Attempts | Result | Notes | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 2 | 3 | 4 | 5 | 6 | ||||||||
| align=left | align=left | | 73.88 | 67.82 | 74.11 | x | 73.62 | 68.72 | 74.11 | ||||
| align=left | align=left | | 68.34 | 72.47 | 72.98 | 68.88 | x | 70.82 | 72.98 | ||||
| align=left | align=left | 70.94 | 69.07 | 71.91 | 67.55 | x | x | 71.91 | |||||
| 4 | align=left | align=left |  | 64.63 | x | 68.19 | 69.23 | 71.40 | 70.21 | 71.40 | |||
| 5 | align=left | align=left |  | 67.31 | x | 64.75 | x | 68.07 | 70.60 | 70.60 | |||
| 6 | align=left | align=left | | 70.39 | 67.25 | 66.52 | 62.74 | 68.62 | 67.90 | 70.39 | |||
| 7 | align=left | align=left | 69.65 | 70.02 | 67.33 | 70.14 | x | 69.57 | 70.14 | ||||
| 8 | align=left | align=left |  | 63.28 | 65.58 | 67.34 | x | x | 68.33 | 68.33 | |||
| 9 | align=left | align=left |  | x | 61.63 | 67.11 | 67.11 | ||||||
| 10 | align=left | align=left | | 66.97 | x | 64.66 | 66.97 | ||||||
| 11 | align=left | align=left |  | x | x | 64.74 | 64.74 | ||||||
| 12 | align=left | align=left | x | 62.76 | 62.35 | 62.76 | |||||||
15 July
| Rank | Name | Nationality | Attempts | Result | Notes | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 2 | 3 | ||||||||
| 1 | align=left | align=left | 70.99 | - | - | 70.99 | Q | |||
| 2 | align=left | align=left | | 70.35 | - | - | 70.35 | Q | ||
| 3 | align=left | align=left | | 67.44 | 68.43 | 66.95 | 68.43 | q | ||
| 4 | align=left | align=left | 68.03 | x | 67.44 | 68.03 | q | |||
| 5 | align=left | align=left | | 64.99 | 67.64 | x | 67.64 | q | ||
| 6 | align=left | align=left | | 66.89 | 65.85 | x | 66.89 | |||
| 7 | align=left | align=left |  | 65.79 | x | x | 65.79 | |||
| 8 | align=left | align=left | 24.50 | 65.23 | x | 65.23 | ||||
| 9 | align=left | align=left |  | x | 64.32 | x | 64.32 | |||
| 10 | align=left | align=left |  | 63.69 | 59.38 | x | 63.69 | |||
| align=left | align=left | x | x | x | NM | |||||
| align=left | align=left |  | x | x | x | NM | ||||
| Rank | Name | Nationality | Attempts | Result | Notes | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 2 | 3 | ||||||||
| 1 | align=left | align=left | | 69.20 | 72.22 | - | 72.22 | Q | ||
| 2 | align=left | align=left | | 70.76 | - | - | 70.76 | Q | ||
| 3 | align=left | align=left | x | 60.47 | 70.71 | 70.71 | Q | |||
| 4 | align=left | align=left | | 69.65 | - | - | 69.65 | Q | ||
| 5 | align=left | align=left | | 50.96 | 65.82 | 69.22 | 69.22 | q | ||
| 6 | align=left | align=left | | 66.53 | 68.65 | 61.97 | 68.65 | q | ||
| 7 | align=left | align=left | | x | x | 67.31 | 67.31 | q | ||
| 8 | align=left | align=left |  | x | x | 66.87 | 66.87 | |||
| 9 | align=left | align=left | | 66.41 | x | 65.49 | 66.41 | |||
| 10 | align=left | align=left |  | 66.05 | x | 65.00 | 66.05 | |||
| 11 | align=left | align=left | | 63.94 | 64.52 | 65.53 | 65.53 | |||
| 12 | align=left | align=left |  | 61.22 | 61.21 | 61.61 | 61.61 | |||
According to an unofficial count, 24 athletes from 18 countries participated in the event.