Initially heading in a southeasterly direction, but subsequently turning eastwards, the Modenbach flows through the valley named after it towards the gently rolling vineyard country by the German Wine Route. It reaches them above the village of Hainfeld, after having broken through the rim of the low mountain range between the Teufelsberg (right; 597.6 m) and the Blättersberg (left; 613.2 m). Below Hainfeld it turns northeast and, passing Edesheim, the stream leaves the hill country and flows through the western part of the Upper Rhine Plain. Three kilometres below Freisbach it is joined from the right by its largest tributary, the Bruchbach.