Rheinbreitbach is located at the north end of the Middle Rhine and at the southern edge of the Siebengebirge. As a whole it is part of the Rhine Westerwald Volcanic Ridge (Rheinwesterwälder Vulkanrücken). The dimensions of its territory are approximately 7 (east-west) by 2 kilometres, its highest point is 375 m, near the summit of the Asberg. Most of the 6,58 km2 area is forested (56.6%) and only a small portion is used agriculturally (8.5%).