Athletics at the 1956 Summer Olympics – Men's 100 metres

This was the thirteenth time the event was held, having appeared at every Olympics since the first in 1896. None of the finalists from 1952 returned. Notable entrants were Americans Bobby Morrow (NCAA champion, U.S. Olympic trial champion, and heavy favorite) and Ira Murchison (world record co-holder); Dave Sime was injured and did not make the American team.[3]

The Bahamas, Ethiopia, Indonesia, Liberia, Malay, Singapore, and Ethiopia were represented in the event for the first time. In addition, German athletes competed as the "United Team" for the first time, though pre-World War II Germany had competed many times and West Germany had competed as "Germany" in 1952. The United States was the only nation to have appeared at each of the first thirteen Olympic men's 100 metres events.

The event retained the four round format from 1920 to 1952: heats, quarterfinals, semifinals, and a final. There were 12 heats, of 4–6 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.[3]

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

World record	10.1	Willie Williams	Berlin, Germany	3 August 1956
	10.1	Ira Murchison	Berlin, Germany	4 August 1956
	10.1	Leamon King	Ontario, United States	20 October 1956
	10.1	Leamon King	Santa Ana, United States	27 October 1956
Olympic record	10.3	Eddie Tolan	Los Angeles, USA	1 August 1932
	10.3	Ralph Metcalfe	Los Angeles, USA	1 August 1932
	10.3	Jesse Owens	Berlin, Germany	2 August 1936
	10.3	Harrison Dillard	London, United Kingdom	31 July 1948

Despite headwinds, Ira Murchison and Bobby Morrow each equalled the Olympic record of 10.3 seconds (hand-timed) in the quarterfinals. Morrow did it again in the semifinals.