Track and field at the 2015 Military World Games – Men's 400 metres

The men's 400 metres event at the 2015 Military World Games was held on 5 and 6 October at the KAFAC Sports Complex.

Records
Prior to this competition, the existing world and CISM record were as follows:

Round 1
Qualification: First 3 in each heat (Q) and next 6 fastest (q) qualified for the semifinals.

Semifinals
Qualification: First 2 in each heat (Q) and next 2 fastest (q) qualified for the final.