Saint-Romain-en-Viennois is a commune . It is found in the region Provence-Alpes-C Ã te d'Azur in the Vaucluse department in the south of France .
Saint-Romain-en-Viennois is a commune in the Vaucluse department in the Provence-Alpes-C Ã te d'Azur region in southeastern France .