Guépratte was retired on 30 August 1918 and took up a career as a politician. He was elected to the National Assembly of France on 16 November 1919 on a left-wing list. He specialised in parliamentary affairs of the Navy. He retired from political life in 1924. He died in Brest in 1939. Guépratte's tomb is in Les Invalides, where French military heroes are buried. A street in Belgrade is named after him.