Swimming at the 2013 World Aquatics Championships – Men's 400 metre freestyle

The men's 400 metre freestyle event in swimming at the 2013 World Aquatics Championships took place on 28 July at the Palau Sant Jordi in Barcelona, Spain.

Records
Prior to this competition, the existing world and championship records were:

Heats
The heats were held at 10:16.

Final
The final was held at 18:13.