The men's 200 metres at the 1988 Summer Olympics in Seoul, South Korea had an entry list of 72 competitors from 59 nations, with ten qualifying heats (72), five quarterfinal races (40) and two semifinals (16), before the final (8) took off on Wednesday September 28, 1988. The maximum number of athletes per nation had been set at 3 since the 1930 Olympic Congress. The event was won by Joe DeLoach of the United States, beating his teammate and defending champion Carl Lewis by 0.04 seconds in the final. The defeat ended Lewis's hopes of repeating his 1984 quadruple, despite running the final under his own Olympic record time. It was the United States' 14th victory in the men's 200 metres. Lewis was the seventh man to win multiple medals in the event, matching Andy Stanfield for the best result to that point. Robson da Silva earned Brazil's first medal in the event with his bronze.

The 1988 Summer Olympics, officially known as the Games of the XXIV Olympiad and commonly known as Seoul 1988, was an international multi-sport event held from 17 September to 2 October 1988 in Seoul, South Korea. 159 nations were represented at the games by a total of 8,391 athletes. 237 events were held and 27,221 volunteers helped to prepare the Olympics.