Abstract Most studies equate children's mental health to a state of flourishing, which is a positive feeling and functions in their lives. Identity exploration and the satisfaction of three basic psychological needs are universal and crucial indicators of children's flourishing. First, according to identity crisis theory, children in the pre-adolescence period begin to explore their own identities, a process which significantly affects their development and flourishing. Meanwhile, self-determination theory points out that the basic psychological needs, namely the needs for autonomy, competence, and relatedness, are essential for children's development and flourishing in the worldwide. Accordingly, this study examined how identity exploration affects the flourishing of rural children in China, one kind of collectivism cultural contexts, with the interaction effect of identity exploration and basic psychological needs satisfaction. To understand the interaction effect of identity exploration and basic psychological needs satisfaction on rural children's flourishing, we form a theoretical framework combining identity crisis theory and self-determination theory. Both these two theories emphasize the importance of self in facilitating mental health and the development of functioning. Specifically, identity crisis theory focuses on intrapsychic process, while self-determination theory stresses the influence of the surrounding environment on the individual, which provides a solid foundation for integrating these two theories to explore rural children's flourishing in China. Accordingly, this study collected 520 left-behind children and 475 other rural children in Liaoning Province in Mainland of China, and used regression analysis to measure the associations among variables. This study found that identity exploration and basic psychological needs satisfaction positively affect rural children's flourishing respectively, while their interaction effects negatively affect on their flourishing.