The present invention concerns the footwear sector and more specifically it concerns a membrane to be fitted as an accessory in the front part or covering the entire surface of the footbed of shoe soles consisting of a support in hydrophilic or breathable and waterproof material onto which a series of suction cups having the shape of an open hourglass or of bellows or of a cylinder are directly moulded in flexible thermoplastic material fitted facing the part where the foot rests in order to provide efficacious ventilation and waterproofing of the shoe and greater comfort during walking.