Abstract: In view of the digital gap in IT products used by aged people, with their digital tax-hailing demand, a research on applying mental model theory and methods in the age-friendly interactive design of digital taxi-hailing products was constructed. Firstly, the mental information of the elderly using digital products to take a taxi was collected, the text of the speech data keywords was encoded and the link node table and process link diagram were obtained. By using the systematic clustering analysis method, the mental node clustering network was generated, and the mental differences and gaps of the elderly in the process of using taxi-hailing digital products were extracted. Secondly, the mental space of the whole process of the elderly using digital products to take a taxi was constructed with the method of combining diagrams. With the product information architecture and functional process design methods, the gaps in the mental space at each stage were filled, the interaction processes were integrated, and a product prototype scheme based on the mentality of the elderly was conducted. Finally, through the usability task test and usability metric evaluation, the usability of the taxi-hailing digital product solution was evaluated. Research results show that the nature of digital products age-friendly design is to fill the gap between the aged people’ mental experience and the ability required by IT product, so as to help guide the elderly to cross the digital divide caused by mental differences.