The men's 400 metres race was the second-shortest of the flat-track events on the Athletics at the 1896 Summer Olympics programme. The competition's preliminary round was the last held on the first day, 6 April. The competitors were split into two groups. The top two runners in each heat advanced to the final, which was held on the second day, 7 April.

At the 1896 Summer Olympics, the first modern Olympiad, twelve athletics events were contested. A total of 25 medals were awarded. The medals were later denoted as 37 modern medals. All of the events except the marathon were held in the Panathinaiko Stadium, which was also the finish for the marathon. Events were held on 6 April, 7 April, 9 April, and 10 April 1896. Altogether, 63 athletes, all men, from nine nations competed. This made athletics the most international of the nine sports at the 1896 Games.