Background: Adolescents were the critical period of physical and mental development, in terms of positive psychology, some internal psychological factors may accelerate the development, given the importance of achievement motivation--the essence of development for adolescents in school and span of life, it may be the key variables to change the trace of the growth, combined with other factors, such as self-efficacy, self-identity, many researchers had explored the association each other, but few authors tested the interaction mechanism of them, especially, hope, the core factor of positive psychology, may be the another variable to affect the mentioned relationship. It was urged to find the interaction mechanism. Objective: The study examined the relation of self-efficacy and achievement motivation, more precisely, the current research estimated mediated effect of self-identity and the moderated effect of hope in the relationship between self-efficacy and achievement motivation. Methods: To fulfil the goal, 473 adolescents participated in the investigation by completing multiple scales in China and diverse analysis methods were used to deal the data. Results: The results showed that self-efficacy significantly linked with achievement motivation, and the self-identity partially mediated the relation between self-efficacy and achievement motivation in adolescents, and the hope moderated the mediating paths. Conclusion: From what mention above, the self-identity and hope, the mediating role and moderator, respectively, were the underlying mechanism of the relationship between self-efficacy and achievement motivation. The strengths and weaknesses based on the study were discussed.