The invention belongs to the technical field of storage of low-temperature liquefied gas media, and relates to a full-volume tank with a non-metal sealing layer for storing a low-temperature medium. The full-volume tank comprises an inner tank, an outer tank, a ceiling, a heat insulation layer and a sealing layer, wherein the heat insulation layer comprises a ceiling heat insulation layer on a ceiling plate, a tank wall heat insulation layer between the inner tank wall and the outer tank wall and a tank bottom heat insulation layer between the inner tank bottom and the outer tank bottom, the tank wall heat insulation layer comprises a first tank wall heat insulation layer and a second tank wall heat insulation layer from outside to inside, the first tank wall heat insulation layer extendsfrom the outer tank wall to the upper surface of the outer tank bottom, and a local angle connection heat insulation layer is formed at the joint of the outer tank wall and the outer tank bottom. According to the full-volume tank, the sealing layer with good liquid tightness and air tightness for sealing the low-temperature medium is arranged, the gasification speed of the leaked liquid is limited, the gasified steam is contained, and the safety of the full-volume tank with the non-metal sealing layer for storing the low-temperature medium is improved.