He was born Gérard Marcel Tisserand, but later adopted the stage name of Souzay from a village on the river Loire. He came from a musical family in Angers, France. His parents had met at one of the first performances of Pelléas et Mélisande in 1902; his mother and two brothers were singers, and his sister, 15 years older, was the soprano Geneviève Touraine, who gave the first performance of Poulenc's Fiançailles pour rire in 1942. After his schooling at the Collège Rabelais in Chinon, he went to the Sorbonne in Paris to study philosophy, and while there he met the singer Pierre Bernac, who encouraged him to study singing. Souzay entered the Paris Conservatoire in 1940, studying with Claire Croiza and Jean-Emil Vanni-Marcoux. He actually began singing as a tenor, but in 1943, with advice from the leading operatic singer Henri Etcheverry, he became a baritone. He graduated from the Conservatoire in 1945 with two first prizes, the Prix de chant and the Prix de vocalise. While at the Conservatoire, he also tried his hand at composition and in 1942 three of his settings of poems by Paul Valéry were given a performance by Pierre Bernac. He went on to study voice with Bernac, although he subsequently expressed some differences with the latter's methods and ideas on pronunciation. He was eager not to limit himself to being a specialist in the French repertoire, and he made a detailed study of German lieder with Lotte Lehmann.