The present study investigated whether and how learning-specific inner speech predicted students' learning strategy and academic performance. Frequencies of inner speech use in specific learning settings were assessed. Four dimensions of inner speech including self-criticism, self-reinforcement, self-management, and social assessment were investigated and linked to the learning strategy and academic performance. Data were collected from both secondary school students and university students. The results indicated that both the cognitive regulative function (self-management) and the affective regulatory function (self-criticism or self-reinforcement) of inner speech contributed to students' learning strategy, while only the cognitive regulative function of inner speech significantly predicted students' academic performance. Furthermore, the prediction of inner speech to academic performance was partly mediated by the learning strategy.