Jules Cavaillès was born at Carmaux on 20 June 1901. After working there as a draughtsman for a mining company, he studied at the Académie Julian in Paris from 1922. In Paris Jules Cavaillès and his wife moved to the la Ruche section, where such luminaries as Chaim Soutine, Amedeo Modigliani and Marc Chagall had lived. Jules Cavaillès became friends with Roger Marcel Limouse, sharing a studio with him for years and joining him at the Louvre to study the Old Masters.
In 1936 Jules Cavaillès was awarded a grant by the Fondation Blumenthal, which made his painting known to a broader public. At the 1937 "Exposition internationale des Arts et Métiers" Cavaillès received a commission to decorate the elaborate Pavillon de Languedoc. That same year he had his first one-man show at the Galerie Druet in Paris.
In 1939 Jules Cavaillès designed a decorative panel for the conference room where the administrative board of La Sequanaise, an insurance company, convened.
During the second world war Jules Cavaillès was an active member of the Résistance; with his friend and colleague Jean Cassou, Cavaillès played a leading role in the Maquis de Languedoc. After the war he was a curator at the Musée des Augustins in Toulouse until he was able to resume teaching at the École des Arts décoratifs in Paris.
From 1946 Jules Cavaillès was once again actively engaged in his own work in both Paris and Tonnerre, producing landscapes, figurative representations and still lifes - which are, to appropriate a remark of Eugène Delacroix's, a "feast for the eye" - and especially interiors with sea views.
Jules Cavaillès showed work at the 1948 Venice Biennale. Many of his works are owned by private collections in France, Italy, Switzerland and the US as well as major public museums world-wide.