Swimming at the 2017 Southeast Asian Games – Men's 400 metre freestyle
# Swimming at the 2017 Southeast Asian Games – Men's 400 metre freestyle

The men's 400 metre freestyle competition of the swimming event at the 2017 Southeast Asian Games was held on 21 August at the National Aquatic Centre in Kuala Lumpur, Malaysia.

## Records

Prior to this competition, the existing Asian and Games records were as follows:

| Asian Record | Sun Yang (CHN) | 3:40.14 | London, Great Britain | 28 July 2012 |
| - | - | - | - | - |
| Games Record | Welson Sim Wee Sheng (MAS) | 3:53.97 | Singapore, Singapore | 11 June 2015 |

## Schedule

All times are Malaysia Standard Time (UTC+08:00)

| Date | Time | Event |
| - | - | - |
| Monday, 21 August 2017 | 09:20 | Heat 1 |
| Monday, 21 August 2017 | 09:20 | Heat 2 |
| Monday, 21 August 2017 | 19:15 | Final |

## Results

### Heats

The heats were held on 21 August.

**Heat 1**


    Source: Heat 1 results

| Rank | Lane | Athletes | Time | Notes |
| - | - | - | - | - |
| 1 | 4 | Aflah Fadlan Prawira (INA) | 03:59.32 | Q |
| 2 | 5 | Tanakrit Kittiya (THA) | 04:01.21 | Q |
| 3 | 3 | Jessie Khing Lacuna (PHI) | 04:01.84 | Q |
| 4 | 6 | Putera Muhammad Randa (INA) | 04:02.30 | Q |
| – | 2 | Hoàng Quý Phước (VIE) | DNS | |

**Heat 2**


    Source: Heat 2 results

| Rank | Lane | Athletes | Time | Notes |
| - | - | - | - | - |
| 1 | 4 | Welson Sim Wee Sheng (MAS) | 03:56.20 | Q |
| 3 | 5 | Pang Sheng Jun (SGP) | 03:59.80 | Q |
| 2 | 7 | Nguyễn Hữu Kim Sơn (VIE) | 04:00.44 | Q |
| 4 | 3 | Yeap Zheng Yang (MAS) | 04:03.09 | Q |
| 5 | 6 | Benedict Boon (SGP) | 04:03.85 | |
| 6 | 2 | Ahnt Khaung Htut (MYA) | 04:31.80 | |

### Final

    Source: Final Results

The final was held on 21 August.

| Rank | Lane | Athletes | Time |
| - | - | - | - |
| | 4 | Welson Sim Wee Sheng (MAS) | 25.20 |
| | 5 | Aflah Fadlan Prawira (INA) | 25.39 |
| | 6 | Nguyễn Hữu Kim Sơn (VIE) | 25.82 |
| 4 | 3 | Pang Sheng Jun (SGP) | 25.90 |
| 5 | 2 | Tanakrit Kittiya (THA) | 26.10 |
| 6 | 7 | Jessie Khing Lacuna (PHI) | 26.26 |
| 7 | 8 | Yeap Zheng Yang (MAS) | 26.38 |
| 8 | 1 | Putera Muhammad Randa (INA) | 26.49 |
