In order to grasp the perceptual information in packaging design more accurately,the pertinence of packaging design and the accuracy of product positioning is enhanced to reduce the consumption of energy, promote the development of China's packaging industry. Through the analysis of the concept and connotation of kansei engineering clearly,the emotion qualification methods of semantic differential analysis and class category analysis in kansei engineering are tested. Taking the mobile packaging as an example,the methods of precision design is applied to obtain the graphics category and their combinations accurately. The methods of precision design are the practical technology,which is based on the common cognition of consumers. This packaging design can obtain the acceptance of a large number of consumers, and will play a great role in the development of the packaging industry and market promotion.