The invention relates to a ventilation or check valve for ventilation or outlet openings of compressed air apparatuses in vehicles, comprising at least one diaphragm disc (2) which is made of flexible material, is held with a central region in a bore of a valve housing and is prestressed with a radially outer region against a valve seat (4) on the valve housing (4) in order to lift off from the valve seat (4) in a pressure-induced manner in the event of a pressure gradient between an input space and an output space or the atmosphere and to open a flow cross section between the input space and the output space or the atmosphere. According to the invention, a plurality of holders (5, 6) are provided on the valve housing (3) as seen in the circumferential direction of the diaphragm disc (2), said holders being arranged at a circumferential distance from one another and locally holding down the radially outer region of the diaphragm disc (2) against the valve seat (4).