Henri Duez was a French professional road cyclist who represented Peugeot throughout the 1960s. A decent climber, Duez began to compete in regional cycling races in the 1950s, winning numerous amateur cups. In 1959 he was part of the French squad that won silver at the 1959 Mediterranean Games in the team road race. The following year he rode for France in the 100 kilometres team time trial at the 1960 Roma Olympics, finishing seventh. Arguably his best result came in 1961 when he won the overall general classification at the Tour of Catalonia. One year later Duez won the second stage of the Critérium du Dauphiné Libéré. During the decade he rode in six editions of the Tour de France with a best result of 14th in 1965. He retired from the sport when he was 28, before founding a driving school.