Osen (sometimes called Steinsdalen) is the administrative centre of Osen Municipality in Trøndelag county, Norway. It is located about northeast of the village of Bessaker (in àfjord Municipality and about south of the village of Seter (by ferry - if driving by road to Seter, it would be over through two other municipalities). Osen Church is located in the village.
The village area is officially named Osen by the Norwegian Mapping Authority. The village area lies in the lower part of the Steinsdalen valley, at the mouth of the river Steinsdalselva, so the village is sometimes called Steinsdalen.