Men’s decathlon at the 1984 USA Championships / U.S. Olympic Trials was held in Los Angeles (Memorial Coliseum) on June 21–22, 1984. Decathlon at those Trials started with an unusually large entry.
Edgars Erinš set a new Latvian record while he improved 8312 points. Latvian previous record belonged to Janis Karlivans with 8271 points (Götzis 2007).