Born in Paris in 1878, André-Gustave was the 5th and last child of his parents, diamond merchant Levie Citroen from the Netherlands and Masza Amelia Kleinman from, Poland.
The Citroen family moved to Paris from Warsaw in 1873. His father committed suicide when André was six years old.
André was a graduate of the École Polytechnique in 1900. In that year he visited Poland, the birthland of his mother, who had recently died. During that holiday he saw a carpenter working on a set of gears with a fish-bone structure.
These gears were less noisy and more efficient. Citroën bought the patent for very little money, leading to the invention that is credited to Citroën: double helical gears. Also reputed to be the inspiration of the double chevron logo of the Citroën brand.
In 1906 he was installed as a director for the Mors company where he was very successful. During World War I, he was responsible for mass production of armaments.
Citroën gained an international reputation during the war, and more as the leading production expert in France. His activities were extensive in connection with the Renault plant, which employed 35,000 men in the manufacture of munitions during the war.
In mid-1919, Citroën was one of the directors of the Société Française Doble, Paris, to build steam cars in France. The design was not feasible and Citroën turned to other projects.
Citroën founded the Citroën automobile company in 1919, leading it to become the fourth-largest automobile manufacturer in the world by the early 1930s (specifically 1932).
Costs for developing the model Traction Avant, which would ironically go on to improve the sales for the company, led to bankruptcy in 1934. It was taken over by the main creditor Michelin, who had provided tires for the cars.
He died in Paris, France, of stomach cancer in 1935 and was interred in the Cimetière du Montparnasse, the funeral being led by the Chief Rabbi of Paris.