Munderfing is a municipality in the district of Braunau am Inn, in the Austrian state of Upper Austria. It lies in the northwestern part of the country, within the Innviertel region bordering Germany.
As a municipality, Munderfing is one of the administrative units that make up the Braunau am Inn district, which is itself part of Upper Austria. The area is part of Austria's Alpine foothills landscape, characterized by rolling terrain and rural surroundings.