Swimming at the 2009 World Aquatics Championships – Men's 400 metre freestyle

The heats for the men's 400 metre freestyle race at the 2009 World Championships took place on Sunday, 26 July at the Foro Italico in Rome, Italy.

Records
The following records were established during the competition:

Heats
Legend: ER: European record; NR: National record

Final
Legend: WR: World record; AF: African record; AS: Asian record; NR: National record