Namdalen () is a traditional district in the central part of Norway, consisting of the municipalities Namsos, Grong, Overhalla, R?yrvik, Fosnes, N?r?y, H?ylandet, Namdalseid, Flatanger, Lierne, Leka, Namsskogan, and Vikna, all in Nord-Tr?ndelag county. The district has two towns: Kolvereid and Namsos.