Curtis "Curt" Melvin Harnett, (born 14 May 1965) is a Canadian racing cyclist. He began cycling as a way to stay in shape for hockey. He competed in four Olympic Games, winning three medals, one silver and two bronze.

Harnett also has three medals from the Commonwealth Games and three medals from the Pan American Games. He held the world record for the 200 metre time trial for 11 years, bested in 2006 by Dutchman Theo Bos. After retiring from cycling in 1996, he attended the Sydney and Athens Olympic Games as a commentator for CBC Sports.

He was inducted into Canada's Sports Hall of Fame in 2005. Harnett was introduced into the Lehigh Valley Velodrome Cycling Hall of Fame. He was the chef de mission for Team Canada at the 2015 Pan American Games and the 2016 Summer Olympics. In 2018, Harnett was made a Member of the Order of Canada.