The work aims to solve the psychological problems of rural young college students based on Gross Theory and use APP as a carrier to interact with users so as to regulate their emotions. The psychological problems of contemporary rural young college students were analyzed and studied by literature research, questionnaires and user interviews. The emotional states of rural young college students in different scenarios were dug deeper based on the Gross Emotion Regulation Theory, so as to analyze the needs and transform them into corresponding functional points and output the design solution based on Gross Theory and APP interaction design construction model. Finally, the usability of the solution was evaluated by Likert five-point scale, and the positive emotion and negative emotion scale (PANAS) was used to verify the positive emotion change of users. The Gross Emotion Regulation Theory is introduced into the interaction design of psychological APP to design an APP for emotion regulation. After tested by users, it can effectively improve users' emotional problems and help them manage their emotions better, and also provides a reference for the design of similar APPs.