Abstract: The current study conducted a questionnaire survey on 802 college students to explore the relation between short video addiction and academic achievement, as well as the mediating role of learning engagement and the moderating role of academic self-efficacy in this relation. The results indicated that: (1) short video addiction negatively predicted college students' academic performance; (2) learning engagement played a partial mediating role in the relation between short video addiction and college students' academic performance, and short video addiction led to the decline of college students' academic performance by reducing learning engagement; (3) academic self-efficacy can significantly moderate the relation between learning engagement and college students' academic performance. That is, the predictive effect of learning engagement on college students' academic performance is stronger in individuals with high academic self-efficacy.