PROBLEM IDENTIFICATION: To evaluate the effects of peer-led supportive interventions for patients with cancer. LITERATURE SEARCH: Six electronic databases (EMBASE, MEDLINE(R), Google Scholar, Cochrane Library, ProQuest Medical Library, and CINAHL(R)) were searched for articles published from 1997 to May 2017. DATA EVALUATION: A total of 159 studies were identified. Eighteen (16 randomized, controlled trials [RCTs] and 2 non-RCTs) were eligible for systematic review and 16 for meta-analysis. The Cochrane risk of bias tool and Comprehensive Meta-Analysis software were used for analysis. SYNTHESIS: The authors synthesized the results of the effect size of each trial according to cancer symptoms, coping, emotional health, quality of life, self-efficacy, sexuality, social support, and health-related behaviors. IMPLICATIONS FOR RESEARCH: The findings from this study suggest that an additional tiered evaluation that has a theoretical underpinning and high-quality methodology is required to confirm the efficacy of peer-led supportive interventions within cancer care models.