Aurach (German pronunciation: [ˈaʊ̯ʁax] ⓘ) is a river in the Bavarian Landkreise (districts) of Ansbach and Roth, Germany.

The Aurach originates about 1 kilometre (0.6 mi) west of Petersaurach, Middle Franconia at an altitude of 452 metres (1,483 ft) above sea level.

It flows to the northern edge of Roth at 325 metres (1,066 ft) above sea level from the left into the Rednitz.

These were for example the Hammerschmiede, Geichsenmühle, Mausenmühle, Steinmühle, Buckenmühle, Hasenmühle, Neumühle, and Hebresmühle as well as those at Gauchsdorf and Rothaurach and the Lohmühle near Roth.

At Petersaurach, Mausendorf, Veitsaurach, Barthelmesaurach, Götzenreuth, Breitenlohe, Aurau, and Rothaurach, the Aurach takes up the purified sewage water from the respective purification plants.