Gaston Marie Léon Cabannes (12 August 1882 – 9 November 1950) was a French politician. Gaston Cabannes was born in Agen. His parents worked in the garment industry and he himself worked as a tailor in Bordeaux. An active trade unionist and a member of the French Section of the Workers' International (SFIO) (French socialist party), Cabannes first stood for election in 1924 on the list of the Cartel des Gauches but was unsuccessful. He was elected to the French Chamber of Deputies representing Bordeaux in the general election of 1932 and was re-elected in 1936. In 1935 he was elected mayor of Floirac.