The men's 400 metres event at the 1996 Summer Olympics in Atlanta, Georgia took place between 26 and 29 July.

Johnson's 400 metres victory in Atlanta was the first of his two wins; he would become the only man to repeat as gold medalist in the event when he won again in 2000.

More generally, his win was the fourth in what would ultimately be 7 consecutive American victories stretching from 1984 to 2008 and the 16th overall title in the event by the United States.

The only two finalists from 1992 to return were bronze medalist Samson Kitur of Kenya and seventh-place finisher Ibrahim Ismail Muftah of Qatar.

Michael Johnson of the United States was the clear favorite, having won the last two world championships.

[2] Algeria, Comoros, Cyprus, Saint Lucia, Slovakia, Sri Lanka, and Yemen appeared in this event for the first time.