# Swimming at the 2019 World Aquatics Championships – Men's 800 metre freestyle

The Men's 800 metre freestyle competition at the 2019 World Championships was held on 23 and 24 July 2019. The defending champion was Gabriele Detti, but he finished 5th in the final. The champion, Gregorio Paltrinieri, was the defending bronze medalist.

## Records

Prior to the competition, the existing world and championship records were as follows.
| World record | Zhang Lin (CHN) | 7:32.12 | Rome, Italy | 29 July 2009 |
| Competition record | Zhang Lin (CHN) | 7:32.12 | Rome, Italy | 29 July 2009 |

## Results
### Heats

The heats were held on 23 July at 11:05.
| Rank | Heat | Lane | Name | Nationality | Time | Notes |
| 1 | 3 | 3 | Gregorio Paltrinieri | Italy | 7:45.70 | Q |
| 2 | 3 | 6 | David Aubry | France | 7:46.37 | Q |
| 3 | 4 | 2 | Jack McLoughlin | Australia | 7:46.42 | Q |
| 4 | 3 | 5 | Gabriele Detti | Italy | 7:46.46 | Q |
| 5 | 4 | 3 | Henrik Christiansen | Norway | 7:46.53 | Q |
| 6 | 4 | 4 | Mykhailo Romanchuk | Ukraine | 7:47.01 | Q |
| 7 | 4 | 1 | Serhiy Frolov | Ukraine | 7:47.25 | Q |
| 8 | 3 | 2 | Sun Yang | China | 7:48.12 | Q |
| 9 | 4 | 7 | Anton Ipsen | Denmark | 7:48.74 | NR |
| 10 | 3 | 7 | Jan Micka | Czech Republic | 7:48.93 | NR |
| 11 | 4 | 5 | Zane Grothe | United States | 7:50.14 | |
| 12 | 4 | 8 | Damien Joly | France | 7:50.30 | |
| 13 | 2 | 4 | Wojciech Wojdak | Poland | 7:50.64 | |
| 14 | 4 | 0 | Mack Horton | Australia | 7:52.65 | |
| 15 | 4 | 9 | Nguyễn Huy Hoàng | Vietnam | 7:52.74 | |
| 16 | 4 | 6 | Jordan Wilimovsky | United States | 7:53.11 | |
| 17 | 3 | 4 | Florian Wellbrock | Germany | 7:53.75 | |
| 18 | 3 | 8 | Ilya Druzhinin | Russia | 7:54.07 | |
| 19 | 3 | 9 | Ákos Kalmár | Hungary | 7:54.55 | |
| 20 | 2 | 6 | Zac Reid | New Zealand | 7:57.46 | |
| 21 | 3 | 1 | Guilherme Costa | Brazil | 7:58.67 | |
| 22 | 2 | 2 | Dimitrios Negris | Greece | 7:58.99 | |
| 23 | 3 | 0 | Vuk Čelić | Serbia | 7:59.17 | |
| 24 | 2 | 5 | Felix Auböck | Austria | 8:02.26 | |
| 25 | 2 | 0 | Aflah Prawira | Indonesia | 8:06.58 | |
| 26 | 2 | 3 | Marwan El-Kamash | Egypt | 8:07.97 | |
| 27 | 2 | 8 | Huang Guo-ting | Chinese Taipei | 8:08.76 | |
| 28 | 2 | 9 | Christian Bayo | Puerto Rico | 8:08.78 | |
| 29 | 2 | 7 | Page Advait | India | 8:10.35 | |
| 30 | 1 | 5 | Glen Lim Jun Wei | Singapore | 8:13.02 | |
| 31 | 2 | 1 | Kim Woo-min | South Korea | 8:14.44 | |
| 32 | 1 | 4 | Cheuk Ming Ho | Hong Kong | 8:15.22 | |
| 33 | 1 | 3 | Joaquín Moreno | Argentina | 8:18.24 | |
| 34 | 1 | 1 | Daniel Jacobs | Aruba | 8:22.96 | |
| 35 | 1 | 2 | Pit Brandenburger | Luxembourg | 8:23.99 | |
| 36 | 1 | 6 | Oil Mortensen | Faroe Islands | 8:24.02 | |
| 37 | 1 | 7 | Franci Aleksi | Albania | 8:33.54 | |
| 38 | 1 | 8 | Filip Derkoski | North Macedonia | 8:35.54 | |

### Final

The final was held on 24 July at 20:02.
| Rank | Lane | Name | Nationality | Time | Notes |
| | 4 | Gregorio Paltrinieri | Italy | 7:39.27 | ER |
| | 2 | Henrik Christiansen | Norway | 7:41.28 | NR |
| | 5 | David Aubry | France | 7:42.08 | NR |
| 4 | 3 | Jack McLoughlin | Australia | 7:42.64 | |
| 5 | 6 | Gabriele Detti | Italy | 7:43.89 | |
| 6 | 8 | Sun Yang | China | 7:45.01 | |
| 7 | 1 | Serhiy Frolov | Ukraine | 7:47.32 | |
| 8 | 7 | Mykhailo Romanchuk | Ukraine | 7:49.32 | |