The invention is to provide a gas mist pressure bath device, which causes to contact carbon dioxide, oxygen or a mixed gas of carbon dioxide and oxygen to the skin or mucous membrane of the head of a living body at pressure higher than a predetermined value for efficiently enabling skin-pass absorption. This device is to cause oxygen, carbon dioxide or a mixed gas of oxygen and carbon dioxide at density higher than a predetermined value to contact the skin or mucous membrane of the head of the living body, and is composed of a gas mist generation means 11 of generating and supplying a mist prepared by pulverizing and dissolving gas and liquid； a compressed air supply means 12 of supplying compressed air； and a living body mask member 13 shaped for covering the head of the living body, having a first sealed layer 14 which is connected to the gas mist generation means 11 and to the compressed air supply means 12, and having a second sealed layer 15 for sealing compressed air supplied from the compressed air supply means 12, so that the gas mist is caused to contact to the skin or mucous membrane of the head of the living body by the second sealed layer 15 at pressure higher than a predetermined value.
