Swimming at the 1984 Summer Olympics – Men's 4 × 100 metre medley relay

The final of the men's 4 × 100 metre medley relay event at the 1984 Summer Olympics was held in Los Angeles, California, on August 4, 1984. 24 teams participated in the heats, with the fastest eight qualifying for the final.

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

The following new world and Olympic records were set during this competition.

Heats
Rule: The eight fastest teams advance to the final (Q).