Abstract: As one of the main methods of gear machining, worm grinding wheel has the advantages of high processing efficiency, stable processing performance and high product quality, which is suitable for mass and specialized gear machining. The diamond grinding wheel is the main dressing tool of worm grinding wheel, and its manufacturing precision spacing determines the machining quality of the gear. Because the diamond grinding roller is made of the hardest material known to man, it is very difficult to trim the tooth profile. Due to the serious loss of dressing tools, optical guidance and manual intervention are mainly used in engineering to achieve machining. This method has low manufacturing accuracy and is difficult to adapt to today’s human needs for gear processing accuracy. For this reason, this paper analyzes the characteristics of tool loss when grinding roller tooth shape trimming, and puts forward a CNC trimming method based on origin offset, and verifies the feasibility of the method through engineering practice.