Abstract: The form of the diamond used for dressing the form grinding wheel has an unnegligible influence upon the dressing accuracy.The following measures may be adopted individually or simultaneously to improve the dressing accuracy: 1 ) Decrease the form error of the diamond, such as choose sharper diamond or sharpen it in case it is dull, polish the diamond into exact radius, etc; 2 ) Decrease the dressing pressure angle v D of the dressing mechanism; 3) Grind the stylus of the dressing mechanism in accordance with the form of the diamond.