Gaston Monnerville (2 January 1897 – 7 November 1991) was a French Radical politician and lawyer who served as the first President of the Senate under the Fifth Republic from 1958 to 1968.

He was not demobilized until 17 July 1940, well after the French defeat by Nazi Germany, and therefore did not vote on the grant of dictatorial powers to Marshal Pétain.

He protested against the armistice signed by Pétain, and complained about the treatment of French colonial subjects by Petain's Vichy government.

As a lawyer in Marseille, in unoccupied France, he defended persons arrested or persecuted by the Vichy government for their opinions or racial origin.

He was defeated for election to the Third Constituent Assembly in November 1946, in part because some Guianese objected to his efforts to close the prison colony of Devil's Island.

[3] He went as far as to use the strong word of forfaiture ("abuse of authority") against the behaviour of Prime Minister Georges Pompidou, who had accepted to sign the referendum project.