The Ruwer is a river in Germany with a length of . It is a tributary of the Moselle. The valley of the Ruwer is a part of the Moselle wine-growing region near Trier in the state of Rhineland-Palatinate. It is famous for its Riesling wines, see Ruwer (region), and, prior to 1 August 2007, the Moselle region used to be known as Moselle-Saar-Ruwer.