Objective: To explore the mediating role of depression in the association between life events and Internet addiction, and to provide evidence for the intervention of Internet addiction. Methods: A total of 3 536 students randomly selected from 3 vocational colleges in Anhui Province completed the questionnaire survey, which included adolescents’ demographic characteristics, the Young Internet Addiction Inventory, the Adolescent Life Events Scale, and the Zung Self-Rating Depression Scale. Results: Of the 3 536 students surveyed, 427 were Internet addicts (12.08%), including 183 boys (14.89%) and 244 girls (10.58%). Negative life events were associated with depression and Internet addiction (r=-0.30，0.28, P<0.01); depression was mediated indirectly between negative life events and Internet addiction. There was statistical significance (a=0.30, b=0.13, P<0.01). Depression-mediated indirect effects accounted for 14.67% of the total effects. Conclusion Depression plays a mediating role in the relationship between negative life events and adolescents’ Internet addiction, suggesting that we can reduce the incidence of Internet addiction by reducing students’ depression through early psychological diagnosis and psychological quality training.