Barbaroux was educated at first by the Oratorians of Marseille, then studied law, and became a successful advocate. He was appointed secretary (greffier) to the commune of Marseille, and in 1792 was commissioned to go to the Legislative Assembly and demand the accusation of the directory of the département of Bouches-du-Rhone, as accomplice in a royalist movement in Arles.
At Paris he was received in the Jacobin club and entered into relations with JP Brissot and the Rolands. It was at his instigation that Marseille sent to Paris the battalion of volunteers which contributed to the insurrection of August 10 1792 against the king. Returning to Marseille he helped to repress a royalist movement at Avignon and an ultra-Jacobin movement at Marseille, and was elected deputy to the Convention by 775 votes out of 776 voting. From the first he posed as an opponent of the Mountain, accused Robespierre of aiming at the dictatorship (September 25, 1792), attacked Marat, and proposed to break up the commune of Paris. Then he got the act of accusation against Louis XVI adopted, and in the trial voted for his death "without appeal and without delay."
During the final struggle between the Girondists and the Mountain, he refused to resign as deputy and rejected the offer made by the sections of Paris to give hostages for the arrested representatives. He succeeded in escaping, first to Caen, where he organized the civil war, then to Saint-Emilion near Bordeaux, where he wrote his Mémoires, which were published in 1822 by his son, and re-edited in 1866. Discovered, he attempted to shoot himself, but was only wounded, and was taken to Bordeaux, where he was guillotined when his identity was established.