An inflatable pneumatic bag is disclosed. An inflatable pneumatic bag includes a pneumatic hole disposed at one end of a pneumatic channel. Air, which is applied to the pneumatic hole, moves along the pneumatic channel, then through air ingress holes covered with inner layers which are removed by the expansion of the outer layers to fill all the air tubes. When the air tube is filled with air, one or more inner layers cover and then close the air ingress hole to overcome reverse air flow. Then, a curve-shaped air passage in the air tube narrows to further prevent air escape. With the inner layer, effectively overcoming reverse air flow, and the air passage, further preventing air escape, the inflatable pneumatic bag filled with air may last for a substantial long period of time.