Purpose To systematically review evidence regarding the benefits of Internet-based psycho-educational interventions among cancer patients. Methods We performed a systematic review with meta-analysis and qualitative evidence synthesis. Systematic searches for published studies in English or Chinese identified eligible randomized and clinical controlled trials. The following databases were searched: Medline, Embase, CINAHL, PsycINFO, Web of Science, Cochrane Central Register of Controlled Trials (CENTRAL), Proquest Digital Dissertations, Foreign Medical Retrieval System, China National Knowledge Infrastructure, China Science and Technology Journal Database, China Wanfang Database, and Taiwanese Airiti Library. We also searched the gray literature and reviewed reference lists from relevant articles. Studies were scored for quality using the Cochrane Risk of Bias Tool. Results Seven eligible studies (1220 participants) were identified that used three intervention tools: website programs (n = 5), e-mail counseling (n = 1), and a single-session psycho-educational intervention (n = 1). The quality of all studies was moderate. The meta-analysis showed that Internet-based psycho-educational interventions had a significant effect on decreasing depression (standardized mean difference (SMD) − 0.58, 95% confidence interval (CI) (− 1.12, − 0.03), p = 0.04) and fatigue (mean difference (MD) − 9.83, 95% CI (− 14.63, − 5.03), p