Swimming at the 1979 Pan American Games – Men's 400 metre freestyle

The men's 400 metre freestyle competition of the swimming events at the 1979 Pan American Games took place on 5 July at the Piscina Olimpica Del Escambron. The last Pan American Games champion was Douglas Northway of US.

This race consisted of eight lengths of the pool, with all eight being in the freestyle stroke.

Results
All times are in minutes and seconds.

Heats
The first round was held on July 5.

Final
The final was held on July 5.