Louis Loucheur (12 August 1872 in Roubaix, Nord – 22 November 1931 in Paris) was a French politician in the Third Republic, at first a member of the conservative Republican Federation, then of the Democratic Republican Alliance and of the Independent Radicals.
Coming from a background in the arms industry, Loucheur became Minister of Armaments in September of 1917. He was administrator of Tréfileries et Laminoirs du Havre (TLH) when he was appointed Minister of Armaments. He replaced Albert Thomas and served as armaments minister until November 26, 1918 when he became Minister of Industrial Re-construction where he remained until January 20, 1920.
Loucheur was briefly Minister of Commerce, Industry, Posts, and Telegraphs under Raymond Poincaré in 1924.
In Édouard Herriot's Second Ministry Loucheur served as Minister of Commerce and Industry and from June 1928 to February 1930. He succeeded Maurice Bokanowski, who had died in an air accident. He then served again under Poincaré as Minister of Labour, Hygiene, Welfare Work, and Social Security Provisions.