In conversations with Claude Glayman, Henri Dutilleux mentioned that during the Nazi’s occupation of France, he had already come to feel that “in my future works I should have to keep my distance from a certain spirit in French music, defined by the worlds of clarity, charm, elegance, balance.” Also, Dutilleux referred that when the time of composing Piano Sonata Op. 1 in 1946-48, it was a period that “I was busy trying to find my own voice”, and “wanted to move gradually towards working in larger forms, and not to be satisfied with short pieces – to get away…from a way of writing that was ‘typically French’”. Among his commentaries show the stereotype of French music given by his contemporaries, and how Dutilleux wanted to shake off this stereotype. The very two factors enabling Dutilleux to make riddance of his so-called “typically French”, according to Caroline Potter, one was Bartók’s methods of musical organization, and the other was the 19th-century Germanic concept of the large-scale masterpiece. Hence this study will use the interviews with Dutilleux, as well as the researches by Potter who knew the composer, as main references, looking into his era and ways of composition, thus reaching an analytical interpretation on this Piano Sonata.