The invention provides a gas buffer bag which is easy to use and has good universality. The gas buffer bag comprises a bag body and a plurality of gas storage chambers are formed in the bag body. The gas storage chamber is provided with a first heat welding spot, a second heat welding spot, a third heat welding spot and a fourth heat welding spot. After inflation, a plurality of first heat welding spot, the second heat welding spot, the third heat welding spot and the fourth heat welding spot are respectively formed into a first fold line, a second fold line, a third fold line, and a fourth fold line. The first fold line and a transverse heat sealing line at an air inlet position of the gas storage chamber formed a first cap. The fourth fold line and the transverse heat sealing line at the air inlet position of the gas storage chamber formed a second cap. The first fold line, the second fold line, the third fold line and the fourth fold line are enclosed to form the gas buffer bag which provides an upper open mouth on the upper end. The first cap and the second cap can close the open mouth of the accommodate cavity respectively along the first fold line and the fourth fold line. The gas buffer bag is convenient to picking and placing and the versatility is good.