The invention discloses a cutting ring.The cutting ring comprises outer splicing blocks and inner splicing blocks.The outer splicing blocks and the inner splicing blocks form a circular ring after being spliced to be matched with a groove of a steel body.The inner splicing blocks are quadrangles in bilateral symmetry.Edges of the lower sides of the quadrangles are arcs.The outer splicing blocks are convex bodies which are in bilateral symmetry and are each provided with a side edge capable of being spliced with one side of the corresponding inner splicing block and the edge of the upper side of the corresponding inner splicing block.The side bottom edges of any two adjacent outer splicing blocks are spliced.The lower bottoms of the spliced outer splicing blocks form an outer circle of the circular ring.The upper bottoms of the spliced outer splicing blocks and the lower bottoms of the spliced inner splicing blocks form an inner circle of the circular ring.Abrasion-resistant layers are arranged on the inner side wall and the outer side wall of the steel body.The thickness ranges of the abrasion-resistant layers are 1 mm to 10 mm.The thickness ranges of the outer splicing blocks and the inner splicing blocks are 5 mm to 10 mm.The invention further discloses a machining method of the cutting ring.In the work process of the cutting ring, borne impact force is gradually weakened, and therefore the service life of the cutting ring is effectively prolonged.