Jan Cornelis "Kees" Douze" (March 30, 1939 in Utrecht – February 24, 2011 in Bilthoven) was a sailor from the Netherlands, who represented his native country at the 1972 Summer Olympics in Kiel, Germany. Kees took the 23rd place in the Finn. Later he specialized in the Star, Dutch national classes as well at the 12 foot dinghy. In 1980 Douze returned to the Olympics as substitute helmsman for the Dutch Star.