Vallée de l'Ernz (Luxembourgish: Ärenzdallgemeng) is a commune in northern Luxembourg, in the canton of Diekirch.

It takes its name from its situation in the valley of the White Ernz river.

The commune of Vallée de l'Ernz was formed on 1 January 2012 from the former communes of Ermsdorf and Medernach.

The law creating the Vallée de l'Ernz was passed on 24 May 2011.

This article related to the geography of Diekirch canton is a stub.