Josiane Bost (born 7 April 1956, in Tournus, France) is a former French racing cyclist who was world road champion in 1977.

Josiane Bost was one of the best female racing cyclists in France in the 1970s.

She won the world championship in 1977 and three national championships on the track, including the unusual combination of pursuit and sprint titles.

She and Geneviève Gambillon, her main rival, bridged the gap in French cycling between Lily Herse and Jeannie Longo.

In 1977, she beat the American, Connie Carpenter, in the world road championship at San Cristóbal.