Five-year survival in childhood cancer has been improved markedly in the past decades. Childhood cancer survivors are at high risk of cardiovascular diseases due to anticancer therapy-induced cardiotoxicity. The comprehensive evidence for the prevention of anticancer therapy-induced cardiovascular disease is, however, sparse. The systematic review described in the protocol aims to summarise the effect of current prevention for anticancer therapy-induced cardiotoxicity among childhood cancer survivors.This protocol is reported in accordance with the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols checklist. We will search PubMed (via Medline), Embase and the Cochrane Library and include the studies investigating the effect of prevention against anticancer therapy-induced cardiotoxicity of childhood cancer. To assess the risk of bias, we will use the Cochrane Collaboration's risk of bias tool for randomised control trials and the Newcastle-Ottawa Scale for cohort studies and case-control studies. Furthermore, we will conduct meta-analyses if there is no substantial clinical heterogeneity between included studies. The Grading of Recommendations, Assessment, Development and Evaluation will be used to evaluate the quality of evidence.Ethical approval is not needed for systematic review of published data. The findings will be published in a peer-reviewed journal and disseminated at scientific conferences.CRD42022333877.© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.