Gregory Henderson (born 10 September 1976) is a New Zealand former professional track and road racing cyclist, who rode professionally between 2002 and 2017. His career includes winning the 15-kilometre (9.3-mile) scratch race at the 2004 world championships and, in road cycling, winning the points competition at the Tour de Georgia in 2005 and 2008.

Henderson rode in five Olympic Games and completed 11 Grand Tours. He also competed in four Commonwealth Games and was a four-time medallist, including winning gold in the points race in 2002. During an important part of his career, he served as André Greipel's main lead-out man, and they were colleagues at both T-Mobile Team and later Lotto–Soudal.

In addition to 17 New Zealand track and road titles and eight World Cup track golds, Henderson has been New Zealand Track Cyclist of the Year (2001, 2002, 2003) and Athlete of the Year, Otago, New Zealand (2001, 2002, 2003).

At the 1998 Commonwealth Games Henderson won bronze medals in the 40-kilometre (25-mile) points race and the 4-kilometre (2.5-mile) team pursuit.

He won gold in the 40-kilometre (25-mile) points race and bronze again in the 4-kilometre (2.5-mile) team pursuit at the 2002 Commonwealth Games.

He won the 15-kilometre (9.3-mile) scratch race at the 2004 UCI Track Cycling World Championships.

At the 2004 Summer Olympics he finished fourth in the points race and seventh in the madison.

His best placing in the 2006 Commonwealth Games was 10th in the scratch race.