Born in 1948, Jean-Louis Blanchou studied at the French National School of Administration (ENA), having graduated from the National Higher School of Agronomic Science (l'Ecole Nationale Supérieure des Sciences Agronomique) in Dijon and the National Higher School of Agronomics (L'Ecole Nationale Supérieure Agronomique) in Montpellier.
He started his career as an engineer at the Ministry of Agriculture and joined the French Home Office in 1982 where he became cabinet director for the Oise region, then for Provence Alpes Côtes D'Azur before being appointed sub-prefect for Châtellerault.
After one year at the State General Accounting Office (Cour des Comptes) in 1988, Blanchou became head of the cabinet office at the Ministry of Trade (1989–90), the Ministry of Justice (1990–92) and the Ministry of Economy and Finance (1992–93). From 1993–96 he was sub-prefect of l'Häy-les- Roses (Val de Marne) and from 1996–99 he was the general secretary for the administration of the Versailles Police force.
Blanchou was appointed director of security at Aéroports de Paris in November 2002.