The Ötztaler Ache is a river in the district of Imst, Tyrol state of Austria.

Including its source rivers Venter Ache [ceb; de; nl; sv] and Rofenache [ceb; de; sv], it is 66.5 kilometres (41.3 mi) long.

The Rofenache is the runoff of the Hintereisferner [ceb; de; nl; sv], a glacier at the foot of the Weißkugel, Ötztal Alps.

At the confluence with the Gurgler Ache [ceb; de; nl; sv] in Zwieselstein [ceb; de; sv], Sölden, the Ötztaler Ache proper is formed.

It flows through Sölden, Längenfeld, Umhausen and Oetz before joining the Inn 8 kilometres (5.0 mi) east of Imst.