Swimming at the 1984 Summer Olympics – Men's 400 metre freestyle

The final of the men's 400 metre freestyle event at the 1984 Summer Olympics was held in the McDonald's Olympic Swim Stadium in Los Angeles, California, on August 2, 1984. The first eight swimmers qualified for the final, while the next eight qualified for the B-final.

Records
Prior to this competition, the existing world and Olympic records were as follows:

The following records were established during the competition:

Heats
Rule: The eight fastest swimmers advance to final A (Q), while the next eight to final B (q).