Incremental belief has been identified to be a strong predictors of students’ learning motivation. Recent research suggested various moderators of its effect. The current study was designed to examine the moderating effects of self-enhancement and self-criticism. It was hypothesized that self-enhancement and self-criticism would interact differently with incremental belief in predicting students’ motivational engagement after academic success and failure. Responses were collected from 440 junior secondary school students in Macau. Results showed that self-enhancement strengthened the effect of incremental belief on students’ effort and persistence after failure. Self-criticism strengthened the effect of incremental belief on persistence after failure, but weakened the effect of effort after success. Reasons are discussed and pedagogical implications are provided.