Abstract: The requirement of an individual fitting garment has become a trend in consumption,and the digitized categorization for garment size designation is a prerequisite for quick realization of an individual fitting garment.In this paper,the men′s suit was taken as an example for mass customization.According to the national garment standard,the method of digitized categorization for garment size designation was explored and developed based on the approaching principle of artificial intelligence.Meanwhile,it was indicated that it was necessary to perfect the garment size designation series of enterprises.The practical effect of the method was validated by a case analysis and corporation application.It offered an effective approach to achieve digitized categorization for garment size designation because of its universal rules for other garment categories.