In this study, we aim to assess the psychological effects of cognitive behavioral therapy (CBT) on internet addiction (IA) in adolescents.This study will search the following databases of Cochrane Library, PUBMED, EMBASE, Scopus, Web of Science, PsycINFO, Chinese Biomedical Literature Database, and China National Knowledge Infrastructure. All these electronic databases will be searched from inception to the September 30, 2019 without any language limitation. Two authors will conduct study selection, data extraction, and study quality assessment, respectively. Any disagreements between 2 authors will be solved by a third author through discussion. Statistical analysis will be performed using RevMan 5.3 software.This study will investigate the psychological effects of CBT on IA in adolescents by measuring psychopathological symptoms, depression, anxiety, time spent on the internet (hours/day), and health-related quality of life.This study summarizes current evidence of CBT on IA in adolescents and may provide guidance for both intervention and future researches.PROSPERO registration number: PROSPERO CRD42019153290.