Dennis Duncan (born January 24, 1945) is a former all-star Canadian Football League running back. After playing college football at Northwestern State University he joined the Montreal Alouettes in 1968 and rushed for 429 yards in his rookie season. The next season was his best in the CFL, with 1037 yards and an eastern All-Star selection. Duncan played a final year in the CFL with the Ottawa Rough Riders, where he rushed for 760 yards and was once again an All-Star. In all, he rushed for 3049 yards in his 4 year, 52 game career.