Purpose: To evaluate the effectiveness of digital interventions for preventing adolescent anxiety. Methods: Two researchers conducted a systematic search of randomized controlled studies of internet-based and computerized interventions for preventing adolescent anxiety in Pubmed, APA PsycInfo, Science Direct, Web of Science, Scopus, The Cochrane Library, CNKI, WanFang Data and CQVIP, and screened the articles, extracted the data and reviewed the quality of the articles based on Cochrane 5.1.0. Meta-analyses were conducted using software Review Manager Version 5.4. Results: A total of 12 articles were included in the meta-analyses. The meta-analyses showed that digital interventions were effective in preventing anxiety (g=0.07, 95% CI 0.02 - 0.12, p = 0.005) and depression (g=0.06, 95% CI 0.01 - 0.11, p = 0.02) in adolescents. Conclusion: Internet-based and computerized interventions are effective in preventing anxiety and depression in adolescents.