Rengsdorf () is a municipality in the district of Neuwied, in Rhineland-Palatinate, Germany. It is situated in the Westerwald, approx. 10 km north of Neuwied.
Rengsdorf is the seat of the ("collective municipality") Rengsdorf-Waldbreitbach.
Today Rengsdorf is a regional well known ("air spa") with popular forest walks. The Rheinsteig, a hiking trail, also passes by the village.
In 1926, an outdoor swimming pool was opened using the water of the small river Völkerwiesenbach, supported by Fritz Henkel, the founder of Henkel. In 1966, it was replaced by a new one, located above the old one.
Lohmann & Rauscher, a developer, producer, and seller of medical devices and hygiene products has one of its headquarters in Rengsdorf (the other one in Vienna, Austria). The headquarter of , a travel operator, is located in Rengsdorf as well as the one of , a confectionery machinery manufacturer. Since 1997, Winkler und Dünnebier SüÃÂwarenmaschinen GmbH belongs to the Maschinenbau Runkel GmbH, a mechanical engineering company that is also seated in Rengsdorf. Other companies with their seat in Rengsdorf are meta Trennwandanlagen GmbH & Co. KG, a manufacturer for cubicle systems, personal and storage lockers and changing rooms and the monte mare Betriebs GmbH, a bath operator.