Below is a list of athletes who competed in both the Summer and Winter Olympics, as of the end of the 2016 Summer Olympic Games.
Prior to the first winter games in 1924, the winter sports of Figure skating and Ice hockey had been contested in the Summer Olympics. The creation of the first winter games allowed for many athletes of the era to compete in both sets of games in the same discipline, and on this page these athletes are listed below the main list. The Russian athlete Nikolai Panin is unique in having competed in both a summer sport (shooting in 1912) and a winter sport (figure skating in 1908) but only competing at the Summer Olympics.
Among athletes who changed sports, the most-occurring combination is bobsledding and athletics, followed by cycling and speed skating. Other events competed in by Summer and Winter Olympians include fencing, track and field, sailing, ski jumping, and equestrian events. Only five of the 128 athletes won medals in both the Summer or Winter Olympics. Eddie Eagan was the only athlete to win gold medals in both the Summer and Winter Olympics. Some of the Olympians competed in both sets of games over a span of different decades.