The utility model belongs to the technical field of the engine, especially, relate to a natural gas engine gaseous ring, including the ring body, to fit with a contraceptive ring at the outer peripheral face of ring body and be equipped with the anchor ring breach, the first side that the ring body was followed to the anchor ring breach is to second side extension, between outer peripheral face central line and second side, be equipped with cladding material in the anchor ring breach, the outer disc molded lines of cladding material includes the straight -line portion that is close to first side and sets up, the pitch arc part of being close to the setting of second side, and the bucket facial height point of the outer disc molded lines of cladding material lies in below the high central line of ring body axial, and it is surface form that the gaseous ring is the asymmetric bucket of rectangle, because the outer disc molded lines of cladding material includes one section circular arc and one section straight line, the bucket facial height point of outer disc molded lines lies in below the high central line of ring body axial, and natural gas engine gaseous ring be the asymmetric bucket face structure of rectangle, can strengthen sealing performance between piston and the cylinder jacket, can reducing wear and prevent the production of scuffing of cylinder bore trouble.