Pierbach is a municipality in the district of Freistadt, in the Austrian state of Upper Austria. It is located in the Mühlviertel region of the country, in the northern part of Austria near the border with the Czech Republic.
As a municipality, Pierbach is one of the constituent local administrative units of the Freistadt district, which lies in Upper Austria's north. The surrounding area is rural and hilly, characteristic of the Mühlviertel's granite landscape.