In 18 years as a professional (1969-87), he won in the 1980 Tour de France and the Vuelta a España in 1979. A testament to the competition at the time, notably Eddy Merckx and Bernard Hinault, Zoetemelk came second in the Tour de France six times. Additionally, he set a record by completing all 16 Tours in which he started. He became the oldest World Cycling Champion in 1985, at 38 and 9 months. After retiring, Zoetemelk became a directeur sportif with Superconflex which became eventually Rabobank in 1996. Zoetemelk stayed with the Rabobank team for 10 years retiring as a directeur sportif and from the sport after the 2006 Vuelta a Espana.
Zoetemelk and his French spouse live in Meaux where they owned and operated a hotel. His son Karl was a French mountain bike rider, being French champion.