The work aims to study the elderly-oriented design of the mobile medical APP interface based on the dynamic characteristics of the needs of elderly users, optimize the interface design strategy, and help the elderly to adapt to the smart medical model under the background of smart elderly care. The web crawler software was used to obtain the online evaluation data of mobile medical APPs for the elderly. The fuzzy Kano model was used to summarize and classify the demand data of the elderly. The subjective weight of needs was determined by AHP, the objective weight of needs was determined by the entropy weight method, and the combined weight of needs was determined by the combination weighting method. According to the weight, the elderly user needs were prioritized, so as to optimize the design of the elderly-oriented interface of mobile medical APPs. This paper applies the user dynamic demand theory to the design of the elderly-oriented interface of mobile medical APPs, attaches importance to the dynamic changes of demand in multiple dimensions such as time and environment, better accesses to the multi-level needs of the elderly, expands the design ideas of elderly-oriented interfaces of mobile medical APPs, and provides references for the research on age-appropriate of mobile medical APPs.