Objective: Theme sand table game is a form of intervention in which children and one or more partners cooperate to set sand tools and complete the process of sand table game work together to condense peer strength, enhance friendship and improve children's mental reading level. Methods: In this study,a single subject a-b-a-b study design was used to implement thematic sandbox intervention on 3 preschool children with weak mental interpretation emotions and basic beliefs, primary false beliefs and secondary false beliefs, and C statistics and visual analysis were used to analyze the effective elements. Results: After the intervention of the themed sand table game, the total scores of the mental interpretation assessment of the 3 children were significantly higher than the baseline scores, and the home interview one week later showed that the intervention had a good maintenance effect, and was significantly better than thebaseline in peer interaction, social skills, character empathy and empathy. Conclusion: Themed sand-board game can effectively improve the mental reading ability of preschool children.