By optimizing the interface mode of medical APP, the sense of operation experience of medical APP for different age groups can be satisfied, so as to improve the efficiency of patients' online medical consultation. Firstly, the analysis of variance was used to demonstrate the rationality of dividing user groups by age. On this basis, the research objects were asked to evaluate the user satisfaction of ten medical APP interface prototypes. With the evaluation results as dependent variables and the elements of each interface prototype as explanatory variables, the linear regression model was used for empirical analysis, and thus the influence of each interface element on user satisfaction was analyzed. The analysis of variance shows that there were significant differences in the sense of operation experience of medical APP among different age groups. Based on the results of empirical analysis, this paper constructs the optimized combination of medical APP interface elements for three age groups, including font style, background frame and interface style. Finally, taking the user group over 60 years old as an example, this paper designs a medical APP interface sample for elderly users.