Trehøje was a municipality (Danish, kommune) in Ringkjøbing County on the Jutland peninsula in west Denmark.
The municipality covered an area of 296 km2, and had a total population of 9,929 (2005).
Neighboring municipalities were Herning and Aulum-Haderup to the east, Holstebro to the north, Ulfborg-Vemb and Ringkøbing to the west, and Videbæk to the south.
It merged with the existing Aulum-Haderup, Herning, and Aaskov municipalities to form the new Herning municipality.
This created a municipality with an area of 1,336 km2 and a total population of 82,935 (2005).