School dropout is a devastating problem leading to negative consequences not only for individuals but also society. Therefore, numerous preventive measures and interventions have been implemented, but the expected outcomes have not been obtained despite vigorous efforts. This may indicate that the dropout process is complicated and not limited to academic issues. Therefore, dropout should be addressed using a more comprehensive approach that integrates personnel as well as cognitive structures like schemas. Here, the relationship between dropout and its possible predictors--insufficient self-control schema and academic self-efficacy--was investigated with 365 high school students. Mediation analysis was conducted via the PROCESS macro. Academic self-efficacy was found to fully mediate the relation between insufficient self-control and dropout, and the indirect effect was also found to be significant. The findings were discussed in the framework of the literature.