Dionys Mascolo (11 February 1916 - 20 August 1997) was a French literary editor, resistance fighter, left-wing political activist, author, and former husband of Marguerite Duras.
With them, Mascolo then founded the groupe de la rue Saint-Benoît and thus joined the Résistance under François Mitterrand using the nom du guerre Lieutenant Masse.
When French President René Coty nominated Charles de Gaulle as prime minister in 1958, Mascolo founded together with Jean Schuster the journal Le 14 juillet; as a mouthpiece of a strengthening Anti-Gaullism.
A vehement opponent of French colonial policy, especially the Algerian War, Mascolo was among the signatories of the Manifesto of the 121 in September 1960.
As a writer, Mascolo was very much concerned with Friedrich Nietzsche and Louis Antoine de Saint-Just; he was also interested in the role of intellectuals, for example, in communism.