Herzogenburg is a town in the district of Sankt Pölten-Land, in the Austrian state of Lower Austria.
It lies in the Traisen valley, a short distance south of the city of Sankt Pölten, the capital of Lower Austria. The town is best known for Herzogenburg Abbey (Stift Herzogenburg), an Augustinian monastery founded in the twelfth century, whose present baroque buildings date largely from the early eighteenth century. The abbey church and its ornate interior are among the notable historic sights in the region.
Herzogenburg is connected to the surrounding area by road and by the railway line running through the Traisen valley toward Sankt Pölten. Its position near the provincial capital places it within easy reach of the wider cultural and administrative centre of Lower Austria.