The Wupper is a tributary to the Rhine river in Northrhine-Westfalia of Germany. It emerges near Meinerzhagen. On its course of about 112 km it traverses the town of Wuppertal where the Schwebebahn Wuppertal runs over the river bed.

The river is not navigable and is located in the former Duchy of Berg. Early industialization profited from water power provided by the many rivulets to the Wupper.

It is crossed by the highest railroad bridge in Germany near Müngsten , close to the Berg castle . The river enters the Rhine river south of Düsseldorf.

Else Lasker-Schüler wrote the drama: Die Wupper.