The Kaiserbach (also called Sparchenbach) is a river of Tyrol, Austria, in the valley Kaisertal in the Kaiser Mountains in the Tyrolean Unterland.

The Kaiserbach rises at about 1,500 m above sea level (NN) near the Stripsenjoch saddle and empties in Untere Sparchen, a quarter of Kufstein, into the Inn.

Felled logs were hauled from many wooded mountainsides in the side valleys of the Kaisertal to the river.

On subsequently opening the lock gates a strong current flowed, enabling the assembled logs to be transported in several stages to Kufstein.

Today all that has survived is the Haupttrift Klause, a restored collection basin on the river bed, and its associated Klaushütte (weir hut) that used to provide worker accommodation.