The Norwegian Institute for Social Research (Norwegian: Institutt for samfunnsforskning, IFS) is a private social science research institute based in Oslo, Norway.
It was founded in 1950 by Vilhelm Aubert, Arne Næss, Eirik Rinde, and Stein Rokkan. It publishes the journal Tidsskrift for samfunnsforskning.
The institute is divided into five research fields, each with its own research director. They are Bernt Aardal (Political institutions, voting and public opinion), Erling Barth (Employment and working conditions), Mari Teigen (Gender and society), Bernard Enjolras (Civil society in transition) and Hilde Lidén (International migration, integration and ethnic relations). In total, the institute has 52 employees.