Bad Marienberg (Westerwald) is a town in the Westerwaldkreis in Rhineland-Palatinate, Germany, and also the seat of the like-named Verbandsgemeinde, a kind of collective municipality.

The Westerwald is a low mountain range on the right bank of the river Rhine in the German federal states of Rhineland-Palatinate, Hesse and North Rhine-Westphalia. It is a part of the Rhenish Massif. Its highest elevation, at 657 m above sea level, is the Fuchskaute in the High Westerwald.