These are the official results of the Men's Decathlon competition at the 1988 Summer Olympics in Seoul, South Korea.

There were a total number of 39 participating athletes, with five competitors who didn't finish the competition.

[1] These were the standing world and Olympic records (in points) prior to the 1988 Summer Olympics.

(*) Original score according to the 1962/1977 tables.

Thompson's mark was not a world record in 1984, but when the 1985 tables came into use, his mark became the record.