Childhood is a critical period to develop healthy behavior habits. The work aims to study how to convey good behavior habits with the help of products, and promote the children's use of product through effective use to form habits in the process of repetition. Based on the persuasion theory, combined feedback and motivation, product design aiming to promote children's behavior was proposed. Stimulating motivation, ensuring new habits within their ability by improving capacity or reducing the difficulty of use, using appropriate means to guide action, and repeating behaviors to transform into habits were all possible ways. In conclusion, three persuasion stages of product design were summarized based on children's cognitive process. The trigger stage focuses on attracting users, the maintain stage focuses on providing support, and the suspend stage focuses on creating expectations. The persuasion process is integrated with fun play to increase user stickiness. This strategy is referred to as TMS-P product design persuasion strategy for children's habit cultivation. This design strategy includes different design methods in different stages. It provides reference for design of children's habit cultivation products.