# 2004 World Junior Championships in Athletics – Men's 400 metres

The men's 400 metres event at the 2004 World Junior Championships in Athletics was held in Grosseto, Italy, at Stadio Olimpico Carlo Zecchini on 13, 14 and 15 July.

## Medalists

| Gold | LaShawn Merritt United States |
| Silver | Nagmeldin Ali Abubaker Sudan |
| Bronze | Obakeng Ngwigwa Botswana |

## Results
### Final

15 July
| Rank | Name | Nationality | Time |
| | LaShawn Merritt | United States | 45.25 |
| | Nagmeldin Ali Abubaker | Sudan | 45.97 |
| | Obakeng Ngwigwa | Botswana | 45.97 |
| 4 | Valentin Kruglyakov | Russia | 46.40 |
| 5 | Serdar Tamac | Turkey | 46.63 |
| 6 | Sean Wroe | Australia | 46.84 |
| 7 | Keith Hinnant | United States | 46.88 |
| 8 | Paulo Orlando | Brazil | 46.95 |

### Semifinals

14 July

#### Semifinal 1

| Rank | Name | Nationality | Time | Notes |
| 1 | LaShawn Merritt | United States | 45.84 | Q |
| 2 | Nagmeldin Ali Abubaker | Sudan | 45.99 | Q |
| 3 | Andrés Rodríguez | Panama | 47.42 | |
| 4 | Michael Gardener | Jamaica | 47.49 | |
| 5 | Manoi Pushpa Kumara | Sri Lanka | 47.65 | |
| 6 | Andretti Bain | Bahamas | 47.86 | |
| 7 | Ruaan Grobler | South Africa | 49.26 | |
| | Renny Quow | Trinidad and Tobago | DQ | IAAF rule 163.3 |

#### Semifinal 2

| Rank | Name | Nationality | Time | Notes |
| 1 | Obakeng Ngwigwa | Botswana | 46.64 | Q |
| 2 | Sean Wroe | Australia | 46.80 | Q |
| 3 | Keith Hinnant | United States | 46.93 | q |
| 4 | Richard Buck | United Kingdom | 47.18 | |
| 5 | Kazunori Ota | Japan | 47.40 | |
| 6 | Damian Kempa | Poland | 47.62 | |
| 7 | Claudio Licciardello | Italy | 48.19 | |
| 8 | Yudai Sasaki | Japan | 48.27 | |

#### Semifinal 3

| Rank | Name | Nationality | Time | Notes |
| 1 | Valentin Kruglyakov | Russia | 46.46 | Q |
| 2 | Serdar Tamac | Turkey | 46.94 | Q |
| 3 | Paulo Orlando | Brazil | 47.02 | q |
| 4 | Željko Vincek | Croatia | 47.08 | |
| 5 | Cory Innes | New Zealand | 47.37 | |
| 6 | Maksim Aleksandrenko | Russia | 47.79 | |
| 7 | Ben Offereins | Australia | 48.25 | |
| | Roger Polydore | Dominica | DNF | |

### Heats

13 July

#### Heat 1

| Rank | Name | Nationality | Time | Notes |
| 1 | Keith Hinnant | United States | 46.54 | Q |
| 2 | Andrés Rodríguez | Panama | 47.02 | Q |
| 3 | Renny Quow | Trinidad and Tobago | 47.19 | Q |
| 4 | Andretti Bain | Bahamas | 47.25 | q |
| 5 | Chris Gebhardt | South Africa | 47.58 | |
| 6 | Morgan Carlington | Jamaica | 48.41 | |
| 7 | Khalid Salem | Saudi Arabia | 49.22 | |
| 8 | Chang Chia-Wei | Chinese Taipei | 50.43 | |

#### Heat 2

| Rank | Name | Nationality | Time | Notes |
| 1 | Nagmeldin Ali Abubaker | Sudan | 46.68 | Q |
| 2 | Cory Innes | New Zealand | 47.31 | Q |
| 3 | Ben Offereins | Australia | 47.54 | Q |
| 4 | Carlos Pérez | Venezuela | 47.68 | |
| 5 | Teddy Venel | France | 47.73 | |
| 6 | Gopal Khatri Chhetri | Nepal | 54.53 | |

#### Heat 3

| Rank | Name | Nationality | Time | Notes |
| 1 | Maksim Aleksandrenko | Russia | 47.47 | Q |
| 2 | Kazunori Ota | Japan | 47.88 | Q |
| 3 | Ruaan Grobler | South Africa | 48.09 | Q |
| 4 | Udomsinachi Erete | Nigeria | 48.70 | |
| 5 | Wilson Lukungu Waiswa | Uganda | 48.73 | |
| 6 | Daryl Vassallo | Gibraltar | 49.38 | |
| 7 | Takeshi Fujiwara | El Salvador | 49.66 | |

#### Heat 4

| Rank | Name | Nationality | Time | Notes |
| 1 | LaShawn Merritt | United States | 46.70 | Q |
| 2 | Sean Wroe | Australia | 47.17 | Q |
| 3 | Damian Kempa | Poland | 47.43 | Q |
| 4 | Roger Polydore | Dominica | 47.43 | q |
| 5 | Cristián Reyes | Chile | 48.14 | |
| 6 | Vasile Bobos | Romania | 48.67 | |
| 7 | Nicholas Mangham | Palau | 58.29 | |

#### Heat 5

| Rank | Name | Nationality | Time | Notes |
| 1 | Serdar Tamac | Turkey | 47.14 | Q |
| 2 | Manoi Pushpa Kumara | Sri Lanka | 47.16 | Q |
| 3 | Paulo Orlando | Brazil | 47.48 | Q |
| 4 | Lukasz Pryga | Poland | 47.93 | |
| 5 | Antti Toivonen | Finland | 48.09 | |
| | Félix Martínez | Puerto Rico | DQ | IAAF rule 163.3 |

#### Heat 6

| Rank | Name | Nationality | Time | Notes |
| 1 | Valentin Kruglyakov | Russia | 46.48 | Q |
| 2 | Richard Buck | United Kingdom | 47.00 | Q |
| 3 | Michael Gardener | Jamaica | 47.06 | Q |
| 4 | Claudio Licciardello | Italy | 47.35 | q |
| 5 | Roman Holly | Slovakia | 47.74 | |
| 6 | Frank Puriza | Namibia | 48.07 | |
| 7 | José Eduardo Acevedo | Venezuela | 48.95 | |

#### Heat 7

| Rank | Name | Nationality | Time | Notes |
| 1 | Obakeng Ngwigwa | Botswana | 46.92 | Q |
| 2 | Željko Vincek | Croatia | 47.68 | Q |
| 3 | Yudai Sasaki | Japan | 47.83 | Q |
| 4 | Mikhail Ratnikov | Belarus | 48.06 | |
| 5 | Mohamed Moussa | Qatar | 48.66 | |
| 6 | Sou Chon Kin | Macau | 51.72 | |

## Participation

According to an unofficial count, 47 athletes from 39 countries participated in the event.
* Australia (2)
* Bahamas (1)
* Belarus (1)
* Botswana (1)
* Brazil (1)
* Chile (1)
* Chinese Taipei (1)
* Croatia (1)
* Dominica (1)
* El Salvador (1)
* Finland (1)
* France (1)
* Gibraltar (1)
* Italy (1)
* Jamaica (2)
* Japan (2)
* Macau (1)
* Namibia (1)
* Nepal (1)
* New Zealand (1)
* Nigeria (1)
* Palau (1)
* Panama (1)
* Poland (2)
* Puerto Rico (1)
* Qatar (1)
* Romania (1)
* Russia (2)
* Saudi Arabia (1)
* Slovakia (1)
* South Africa (2)
* Sri Lanka (1)
* Sudan (1)
* Trinidad and Tobago (1)
* Turkey (1)
* Uganda (1)
* United Kingdom (1)
* United States (2)
* Venezuela (2)