After studying law at the University of Toulouse, Auriol was elected to the French Chamber of Deputies in 1914; he soon emerged as a prominent figure in the Socialist Party, leading its parliamentary delegation between 1919 and 1935. He served as the French premier Léon Blum's minister of finance in 1936–37, voted against granting full administrative powers to Marshal Philippe Pétain (Pétain, Philippe) as head of the Vichy regime in 1940, and was imprisoned between 1940 and 1943.

As minister of state in Charles de Gaulle's Cabinet in 1945, Auriol became known as a mediator of the right and left wings. His conciliatory policy was continued during his presidency, but the stresses in France at the end of the war proved to be overwhelming. Economic depression, factional political disputes, and the French Indochina War provided a basis for consistent attacks from both the communists and the Gaullists. Auriol refused renomination in 1954 and removed himself from politics entirely in 1960.