As the largest third-party payment platform in China, Alipay has joined the team of making the world greener with the embedded cute mini APP--Ant Forest. Why are so many Alipay users willing to plant trees through Ant Forest? What are the motivations that affect their continued planting for months or even years? Based on the previous literature, we outlined a new framework to investigate the motivation in Ant Forest. The data were collected through a pilot study and semi-structured interviews with fourteen Chinese Alipay users; at the same time, they are Ant Forest participants. This article analyzes how intrinsic motivations (enjoyment, fulfillment, altruism, social interaction, identification), extrinsic motivations (external rewards, reciprocity, competition) influencing Chinese users to participate in Ant Forest, and whether these motivations have different influences and relationships when motivating participants. What’s more, we can through intrinsic motivation and extrinsic motivation to know how a mini-app that aggregates multiple features can attract users' continued participation, and give suggestions to the firm.