Gallia Narbonensis was a Roman province located in what is now Languedoc and Provence, in southern France.

It became a province in 121 BC, originally under the name of Gallia Transalpina (Transalpine Gaul). The Romans called it Provincia Nostra ("our province") or simply Provincia ("the province"), a name which has survived in the modern name of the region, Provence. The name Gallia Narbonensis stems from the Roman colony of Narbo Martius (Narbonne) which was founded on the coast in 118 BC.

Bordering directly on Italy, control of the province gave the Roman state several advantages, such as control of the land route between Italy and the Iberian peninsula; a buffer against attacks on Italy by tribes from Gaul; and control of the lucrative trade routes of the Rhone valley, over which commercial goods flowed between Gaul and the trading center of Massalia, modern Marseille.