Rhiannon Leier (born May 30, 1977) is a Canadian former competition swimmer who specialized in breaststroke events. She is a multiple-time Canadian record holder, a two-time finalist at the FINA World Championships (2001 and 2003), and a six-time NCAA All-American honoree. She also won a bronze medal, as a member of the Canadian swimming team, in the women's 4x100-metre medley relay at the 2002 Pan Pacific Swimming Championships in Yokohama, Japan, clocking at 4:05.59. Leier is also the granddaughter of former baseball player, track athlete, and ice hockey player Edward Leier, who played two seasons with the Chicago Blackhawks in the National Hockey League.