The work aims to carry out a case study of product design for multiple categories of Xiaomi product families, explore the composition characteristics of its design genes, study and analyze the difference in identification strength of product design genes, and then form a preliminary method of product design gene extraction and construction, as well as an identification strength analysis method. A product design gene recognition strength comparison method was constructed. Typical samples were selected by the card classification method, the cluster analysis method and the multi-dimensional scale analysis method; Then typical genes were extracted by the questionnaire and design form analysis method; Finally the gene recognition strength differences were comprehensively evaluated by combining the eye tracking and the entropy weight method. A factor library of Xiaomi products (home appliances and smart category) was formed, containing 5 generic genes and 18 specialized genes, and the identification intensity of generic genes was higher than that of specialized genes. A research method for product family design gene identification strength is preliminarily developed based on eye tracking. It can be used as a basis for planning and managing product design solutions, so that the product design can take into account the continuity of brand genes and the rationality of individual product design. It can also provide design strategies and references for ecological chain companies to develop different product categories of the same brand.