Jean-Claude-Républicain Arnoux (Le Cateau-Cambrésis (1792-12-16)16 December 1792 – 1866) was a French civil engineer known for his invention of the Arnoux system for articulating trains on tight curves.
As an entrepreneur he founded and directed the Compagnie de Paris à Orsay, which constructed and operated the line from Paris to Orsay and is now part of the Ligne de Sceaux.