Ferdinand "Ferdi" Kübler (pronounced [ˈfɛrdinand ˈkyːblər]; born 24 July 1919) is a retired Swiss cyclist with more than 400 professional victories, including the 1950 Tour de France and the 1951 World Road Race Championship.
Kubler was born in Marthalen. He began racing professionally in 1940 but his early career was limited to Switzerland by the Nazi occupation elsewhere. He was multiple Swiss national champion and a three time winner of the Tour de Suisse.
He rode the Giro d'Italia from 1950–1952, placing fourth once, and third twice. Kubler abandoned the 1947 and 1949 Tours de France, despite an early stage win in each. In the 1950 Tour, he benefited from the absence of Fausto Coppi, sidelined after a crash in the Giro. Overcoming Gino Bartali, Kubler became champion by over nine minutes, also winning three stages. In the 1954 Tour, Kubler won the points jersey and came second behind Louison Bobet.
Kubler was a high-spirited and impulsive rider sometimes given to strategically unwise attacks, out of exuberance and competitive drive. He was known as "the cowboy" because of his penchant for Stetson hats. He retired from racing in 1957 at 38. He is the oldest living Tour de France winner.