The Seefelder Aach is a river in the districts of Sigmaringen and Bodenseekreis, Tübingen region, southern Baden-Württemberg, Germany.

It is approximately 55 kilometres long and flows into Lake Constance.

It has a catchment area of 279 km2 and is part of the Rhine river system.

[1] The upper part – near Aach-Linz – it is also colloquially called Linzer Aach or Hintere Aach.

This article related to a river in Baden-Württemberg is a stub.