Jørgen Marcussen (born 15 May 1950) is a former Danish racing cyclist.

He competed, as an amateur, in the individual road race and team time trial events at the 1972 Summer Olympics. As an amateur he also became national champion in team time trial in 1970, and in individual time trial in 1975.

From 1976 he rode as a professional, predominantly on less prominent teams.

In the 1978 UCI Road World Championships Jørgen Marcussen created an upset by winning a bronze medal, behind Gerrie Knetemann and Francesco Moser. He also managed to finish 4th overall in the 1981 Vuelta a España, which was the best result by a Dane in a Grand tour at the time. It was a feat that was not expected and not surpassed until Bjarne Riis came 3rd in the 1995 Tour de France.

Jørgen Marcussen is married to Olympic cyclist Karina Skibby.