None of the 1912 medalists returned in 1920. Notable entrants included Charley Paddock of the United States, the 1919 Inter-Allied Championship winner and Olympic favorite; fellow American Loren Murchison, who had defeated Paddock in the U.S. Olympic trials; and Harry Edward of Great Britain, the 1920 AAA Championships winner.

[2] Egypt, Luxembourg, Monaco, New Zealand, Spain, and Switzerland were represented in the event for the first time.

For the first time, Hungary did not compete (a result of not being invited after World War I)—making the United States the only nation to have appeared at each of the first six Olympic men's 100 metres events.

The starter had told Paddock to adjust his position, causing Murchison to stand, thinking the full start sequence would be repeated.

Paddock won by half a metre over Kirksey, with Edward a "chest behind" the silver medalist.