This paper aims to improve and study the man-machine interaction defects of mould case circuit breaker. By changing the interface information layout, the interface information transmission effect was enhanced, with user pressure in information reading reduced. User demand information was acquired based on interview method, observation method and literature reading method. Information was classified by user demand levels according to KJ (affinity diagram) method, with its weight calculated by AHP (analytic hierarchy process) method. Finally, user demand was converted into design requirement by QFD (Quality Function Deployment) method and product improvement design function model was built. Guided by user demand, this paper rationally analyzes the man-machine interaction pain points in mould case circuit breaker, and takes this as the improvement and innovation points to build a functional design model for the improved design of man-machine interaction of mould case circuit breaker, hoping to improve the working efficiency of users, and provide new ideas for the improvement research on man-machine interaction of similar products.