Abstract: The invention relates to a membrane assembly, provided with a carrier which carries a layer of a macromolecular substance with membrane action, said carrier being a composite carrier comprising on the one side a layer (2) having an open, cohesive structure, whereby layer (6) of the macromolecular substance extends into layer (2), and on the other side a supporting layer (3) on the side turned away from layer (6) having membrane action.The carrier comprises, preferably, completely or partially a knitted or woven textile product. The supporting layer (3) is advantageously a plastic non-woven. The macromolecular substance is expediently a polymer, said substance taking care for the connection of the supporting layer (3) to the remaining parts of the composite carrier.A device for the production of the present membrane assembly is also described.