Alexandra Greenfield (born 1990) is a Welsh former road and track cyclist from Barry. She began competing at a young age with the Maindy Flyers children's cycle club before joining Cardiff Ajax CC. Greenfield holds the record for the 5 km Tandem Standing Start event on the track along with Katie Curtis, with a time of 7 minutes 4.424 seconds. The record was set in Newport Velodrome on 10 June 2004.^[2] She transitioned from Wiggle High5's former technical director and assistant directeur sportif, to be Cycling New Zealand's women's endurance assistant coach by mid-2018.^[3]

She became the British junior scratch race champion in 2007 as well as the junior European points race champion. In 2008, Greenfield retained her European points race title and added another title as a member of the junior team pursuit squad. She made her debut to the UCI Track Cycling World Cup Classics in the 2008–2009 season, taking third place in the scratch race in the first round in Manchester.