Katie Mactier (born 23 March 1975 in Melbourne) is an Australian professional racing cyclist. She began racing in 1999 at 24 and was an Australian Institute of Sport scholarship holder. She was educated at Wesley College, Melbourne. She is a member of the Carnegie Caulfield Cycling Club. She lives in Melbourne, Australia with her 2 Children, Charlie & Lachie. In 2001 Mactier won in the national road championship. In 2002/2003 she was the Australian pursuit champion, and second in the 2003 world pursuit championship. She was 2003 and 2005 Australian Female Track Cyclist of the Year.