Kloster Mariabrunn, Penzing, Monastery and museum in Penzing district, Vienna, Austria

Kloster Mariabrunn is a former Augustinian Discalced monastery at Hauptstraße 7 in Hadersdorf-Weidlingau, Penzing. The early Baroque two-storey rectangular complex is divided by a central cross-wing into two unequal courtyards, with the parish and pilgrimage church of Mariabrunn attached diagonally at the southwest corner.

The monastery was completed in 1655 by architect Domenico Carlone as a religious center for the region. Major expansions between 1726 and 1739 likely included design work by Lucas von Hildebrandt on the cross-wing section.

Pilgrimage at Mariabrunn is documented from 1610; in 1636/1637 Emperor Ferdinand II handed the site to the Discalced Augustinians, who completed church and monastery in 1655. From 1822 to 1847 professional runners raced from Vienna to Mariabrunn and back each 1 May, a public event tied to the site.

Today the monastery buildings house a federal research and training center focused on forestry and natural resources on Hauptstrasse 7. Access may be limited since the building serves as a working facility, though parts of the courtyard are often visible from the street entrance.

From 1813 to 1875 this site housed Austria's Imperial Forestry Institute, making it a key location in the country's scientific development before later becoming part of a natural resources university. This unexpected connection between a pilgrimage church and forestry research shaped much of its later purpose.