The Lignon (French pronunciation: [liɲɔ̃]) is a 20.7 km (12.9 mi) long river in the Ardèche département, southern France. Its source is at La Souche, in the Parc naturel régional des Monts d'Ardèche. It flows generally east-northeast. It is a right tributary of the Ardèche into which it flows between Meyras and Pont-de-Labeaume.

This list is ordered from source to mouth:

• Ardèche: La Souche, Jaujac, Fabras, Meyras, Pont-de-Labeaume