The men's 100 metres sprint event at the 1948 Olympic Games in London, England, we held at Wembley Stadium on 30 and 31 July.

[2] The photo finish equipment consisted of a photoelectric cell, called the Magic Eye, produced by Swiss watchmaker Omega and a slit photography camera produced by the British Race Finish Recording Company.

Notable entrants and favorites were American Mel Patton and Panamanian Lloyd LaBeach.

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.