The men's 4 × 400 metres relay was a track and field athletics event held as part of the Athletics at the 1912 Summer Olympics programme.

Twenty-eight runners from seven nations competed.

[1] NOCs could enter 1 team of 4 athletes, with up to 2 reserves.

Great Britain, in the first semifinal, set the inaugural Olympic record with 3:19.0.

In the final, the United States set a new world record with 3:16.6.