The sinkhole opened up at 18:30 on Monday evening, local time. Video clips from passing cars show how a man on a motorcycle falls into the suddenly appearing hole.
The rescue service carried out an extensive search effort for 17 hours after the man, who was in his 30s, where personnel wore wetsuits and "dug with their hands" together with a search dog.
On Tuesday, the man was found dead at a depth of about 90 centimeters in the hole, which measures 20 meters wide and 20 meters deep.
An investigation has been initiated into the cause of the sinkhole. It occurred near a construction site where the subway is being expanded and it could be one of "several possible contributing factors", says a spokesperson for Seoul City.
