ABSTRACT: BACKGROUND: Adolescence is a transition period that involves physiological, psychological, and social changes. Emotional problems such as symptoms of anxiety and depression may develop due to these changes. Although many of these problems may not meet diagnostic thresholds, they may develop into more severe disorders and may impact on functioning. However, there are barriers that may make it difficult for adolescents to receive help from health professionals for such problems, one of which is the limited availability of formal psychological therapy. One way of increasing access to help for such problems is through self help technology (i.e. delivery of psychological help through information technology or paper based formats). Although there is a significant evidence base concerning self help in adults, the evidence base is much weaker in adolescents. This study aims to examine the effectiveness of self help technology for the treatment of emotional problems in adolescents by conducting a systematic review of randomized and quasi-experimental evidence. METHODS: Five major electronic databases were searched: Medline, PsycInfo, Embase, Cochrane Controlled Trials Register and CINAHL. In addition, nine journals were handsearched and the reference lists of all studies were examined for any additional studies. Fourteen studies were identified. Effect sizes were calculated across 3 outcome measures: attitude towards self (e.g. self esteem); social cognition (e.g. self efficacy); and emotional symptoms (i.e. depression and anxiety symptoms). RESULTS: Meta analysis showed small, non-significant effect size for attitude towards self (ES = -0.14, 95% CI = -0.72 to 0.43), a medium, non-significant effect size for social cognition (ES = -0.49, 95% CI = -1.23 to 0.25) and a medium, non-significant effect size for emotional symptoms (ES = -0.47, 95% CI = -1.00 to 0.07). However, these findings must be considered preliminary, because of the small number of studies, their heterogeneity, and the relatively poor quality of the studies. CONCLUSION: At present, the adoption of self help technology for adolescents with emotional problems in routine clinical practice cannot be recommended. There is a need to conduct high quality randomised trials in clearly defined populations to further develop the evidence base before implementation.