Marcel Valentin-Louis-George-Eugene Proust was born in Auteuil as the son of an eminent doctor, Adrien Proust, and his wife, Jeanne Weil, who was from an Alsatian Jewish family. He attended the Lycée Condorcet (1882-1889) and in spite of his severe asthma did his one year military service at Orléans. He then studied law at the Sorbonne and the École des Sciences Politiques. He published his first works, 'Portraits de Peintres' and 'Plaisirs et les Jours', in 1896. Proust's unpublished works from this period, 'Jean Santeuil', (an autobiographical work which was never finished) and 'Contre Sainte-Beuve', (the latter an attack of the criticism of Sainte-Beuve), were discovered in the 1950s.

His earliest love affairs, which had been heterosexual, changed later into homosexual affairs. Among them was Alfred Agostelli, who was married and was killed in an air accident. To the age of 35 Proust lived the life of a social climber in the Paris salons, although he worked for a short time as a lawyer and was also active in the Dreyfuss affair like Émile Zola and other artists and intellectuals.

When Proust's father died in 1903 and his mother in 1905, he withdrew gradually from society, lived in a sound-proof flat devoted himself on the Boulevard Haussmann; there he chiefly to writing and introspection. From 1910 he spent much time in his cork-lined bedroom, often sleeping in the day and working in the night. In 1912 Proust produced the first volume of his seven part major work, 'Á la Rechere du Temps Perdu' (in search of lost time). The second book, which was delayed by the WW I, appeared in 1919, and the next parts made him internationally famous. The massive work occupied the last decade of his life and is regarded as one of the greatest achievements of Western imaginative literature.