The men's marathon at the 2012 Olympic Games in London took place on the Olympic marathon street course on 12 August, the final day of the Games. One hundred and five athletes from 67 nations competed. The event was won by Stephen Kiprotich of Uganda, the nation's first Olympic men's marathon victory and the nation's only medal in 2012. Kenya earned its fourth and fifth medals in five Games, with Abel Kirui's silver and Wilson Kipsang's bronze.

Mebrahtom "Meb" Keflezighi (; is a retired American long distance runner. He is the 2004 Olympic silver medalist in the marathon and finished in fourth place in the 2012 Summer Olympics. He won the 2009 New York City Marathon on November 1, 2009, and the 2014 Boston Marathon on April 21, 2014, becoming the first American man to win each race since 1982 and 1983, respectively. Keflezighi is a graduate of UCLA, where he won four NCAA championships competing for the UCLA Bruins track and field team. He came in fourth in the 2014 New York City Marathon on November 2, 2014, eighth in the 2015 Boston Marathon on April 20, 2015, and second in the 2016 U.S. Olympic Team Trials to qualify for the 2016 Summer Olympics.