(French: “Coalition of the Left”), in the French Third Republic (1870–1940), a coalition of left-wing parties in the Chamber of Deputies (lower house of the legislature). It governed France from 1924 to 1926.

The Socialist Party, which usually disdained association with the bourgeois parties of the right, joined an electoral alliance with the Radicals, who had dominated prewar ministries. Together they formed the Cartel in opposition to the Bloc National—the right-wing nationalist group elected at the end of World War I—and defeated it in the elections of May 11, 1924. In the victory they gained more than 300 seats to 200 for the Bloc National and then set up a cabinet under the Radical leader Édouard Herriot. In an attempt to unify the left, the Radical leaders followed a policy of anticlericalism, trying to enforce secular education in strongly religious Alsace-Lorraine, which had been recently recovered from Germany. In international affairs, a policy of security through negotiation (in contrast to the militant stance of the Bloc National) was pursued by the foreign minister Aristide Briand.

A financial crisis caused by continuing inflation led to the Cartel's downfall. The Socialists, demanding a direct tax to meet government expenses, found themselves in disagreement with the Radicals, who hesitated to move in any direction, especially in support of a proposal so violently opposed by business interests. On April 10, 1925, the Herriot government fell. Succeeding ministries under Paul Painlevé and Briand were able neither to solve the financial problem nor to maintain the fragile unity of the Cartel.