Gentin was Minister of Posts, Telegraphs, and Telephones from 18 January 1938 to 13 March 1938 in the 4th cabinet of Camille Chautemps.
During World War II (1939-45), in October 1939 Gentin said that manufacturing for the military should not be allowed to affect production of luxury goods, since the profits from exports would offset the cost of war material imports.