After passing the agrégation examination in 1920, Louis Renou taught for a year at the lycee in Rouen. He then took a sabbatical, read the works of Sanskrit scholars and attended the classes of Antoine Meillet. Henceforth he opted exclusively for the study of Sanskrit. He attended the lectures of Jules Bloch at the Ecole des hautes etudes. The work he did at this time gave rise to Les maitres de la philologie vedique (1928). His doctoral thesis, submitted in 1925, was La valeur du parfait dans les hymnes vediques. After a short time at the Faculte de lettres in Lyon, he moved to L'ecole des hautes etudes and then to the Sorbonne where he succeeded Alfred A. Foucher. In 1946 he was elected to the Academie des Inscriptions.
In the following years he undertook three journeys: India in 1948-1949, Yale University in 1953, and Tokyo in 1954-1956 where he was director of the Maison franco-japonaise. He hardly travelled after this.
He had settled on his line of study early on and never wrote about any subject other than India. He left to one side archaeology, political history and Buddhism and concentrated firmly on the tradition that, beginning with the Rig Veda, runs through all aspects of belief and practice right up to the present. For forty years he regularly published articles and books that were often voluminous, were based on original research, and are of considerable merit. The study of the Indian theory of grammar lies at the heart of his work. This can be seen in the Etudes vediques et panineennes published between 1955 and 1966. The Etudes consist of more than two thousand pages of translation and commentary of Vedic hymns. The Etudes covered two thirds of the Rig Veda by the time of his death.
Louis Renou was director of the Institut de civilisation indienne and attended regularly meetings of the Academie and the Societe Asiatique. He died in 1966.
- In English
- Religions of Ancient India, (1968), Schocken Books ISBN 0-8052-0179-3
- History of Vedic India. New Delhi, Sanjay Prakashan, 2004, xi, 216 p., ISBN 81-7453-102-5
- Hinduism, (1961), George Braziller, ISBN 0-8076-0164-0
- A History of Sanskrit Language, (translated by Balbir, Jagbans Kishore) (2003) ISBN 81-202-0529-4
- In French (selected publications only)
- L’Inde classique : manuel des études indiennes, with Jean Filliozat, Paris : Payot, 1947
- L’Inde classique : manuel des études indiennes, with Jean Filliozat, vol. II (with Paul Demiéville, Olivier Lacombe and Pierre Meile), Paris : Imprimerie Nationale, 1953
- Aṣṭādhyāyī La grammaire de Pāṇini Paris : École française d’Extrême-Orient, 1966
- L'Inde fondamentale Hermann, Collection Savoir, c1978. ISBN 2-7056-5885-8.
- Louis Renou : choix d'études indiennes Paris : École française d'Extrême-Orient, 1997. (2 vol.)
- Notes sur la version « Paippalada » de l'atharva-veda, Paris : imprimerie nationale 1964
- Sur le genre du Sutra dans la littérature sanskrite, Paris : imprimerie nationale 1963
- Littérature sanskrite, A.Maissonneuve 1946
- Grammaire et Vedanta, Paris imprimerie nationale 1957
- Fragments du Vinaya Sanskrit, Paris : imprimerie nationale 1911
- Etudes védiques, Paris : imprimerie nationale 1952
- Etudes védiques et paninéennes (2 volumes), Paris: imprimerie nationale 1980-1986
- Anthologie sanskrite, Paris : Payot,1961
- Benveniste, Émile. Notice sur la vie et les travaux de M. Louis Renou, published in Louis Renou, choix d'etudes indiennes/Reunies par N. Balbir & G.-J. Pinault., Paris: presses de l'Ecole francaise d'extreme orient. 1997, 2 volumes. ISBN 2-85539-562-3.