The men's 400 m freestyle swimming events for the 2016 Summer Paralympics took place at the Olympic Aquatics Stadium from 8 to 15 September.
A total of seven events were contested for seven different classifications.
Each event consists of two rounds: heats and final.
The top eight swimmers overall in the heats progress to the final.
If there are eight or fewer swimmers in an event, no heats are held and all swimmers qualify for the final.