Athletics at the 1948 Summer Olympics – Men's 100 metres

This was the eleventh time the event was held, having appeared at every Olympics since the first in 1896. With a 12 year gap due to World War II, none of the athletes from the 1936 edition returned. Notable entrants and favorites were American Mel Patton and Panamanian Lloyd LaBeach. American Barney Ewell was a "top sprinter" but "felt to be slightly past his prime." The third member of the United States team was Harrison Dillard, a hurdles specialist who had also entered the 100 metres and came in third at the U.S. Olympic trials.[4]

Bermuda, Burma, Guyana, Iraq, Jamaica, Pakistan, Panama, Trinidad and Tobago, and Uruguay were represented in the event for the first time. The United States was the only nation to have appeared at each of the first eleven Olympic men's 100 metres events.

The event retained the four round format from 1920–1936: heats, quarterfinals, semifinals, and a final. There were 12 heats, of 4–7 athletes each, with the top 2 in each heat advancing to the quarterfinals. The 24 quarterfinalists were placed into 4 heats of 6 athletes. The top 3 in each quarterfinal advanced to the semifinals. There were 2 heats of 6 semifinalists, once again with the top 3 advancing to the 6-man final.[4]

Prior to the competition, the existing world and Olympic records were as follows.

World record	10.2	Jesse Owens (USA)	Chicago, United States	20 June 1936
	10.2	Harold Davis (USA)	Compton, United States	6 June 1941
Olympic record	10.3	Eddie Tolan	Los Angeles, USA	August 1, 1932
	10.3	Ralph Metcalfe	Los Angeles, USA	August 1, 1932
	10.3	Jesse Owens	Berlin, Germany	August 2, 1936

Harrison Dillard of the United States matched the Olympic record in the final.

All times are British Summer Time (UTC+1).

• Organising Committee for the XIV Olympiad, The (1948). The Official Report of the Organising Committee for the XIV Olympiad. LA84 Foundation. Retrieved 4 September 2016.