Background: The relationship between religiosity and gambling behaviors presents a complex and multifaceted picture. Prior research has yielded mixed results, highlighting the need to examine existing literature systematically. This systematic review and meta-analysis aim to explore the correlation between various levels of religiosity and gambling behaviors and attitudes among adolescents and adults. It also seeks to understand how socio-demographic, religious, and gambling-related factors, as well as methodological characteristics of studies, moderate this relationship.Methods: The review, including a meta-analysis, will be conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. It will include peerreviewed empirical studies involving adolescents and adults, and using measures of religiosity and gambling at the individual level. Studies such as meta-analyses, technical reports, study protocols, theoretical articles, preprints, conference abstract, book chapters, Ph.D. dissertations or MA theses and those reporting secondary data or involving gambling-like activities will be excluded. We will search Scopus, Web of Science, PsycINFO, PsycTESTS, PsycTHERAPY, PsycARTICLES, ERIC, and Medline. Risk of bias in the included studies is assessed through established methods. The synthesis of results comprises two approaches: narrative synthesis, suitable for both qualitative and quantitative research, and a meta-analysis for quantitatively synthesizing correlations between religiosity and gambling. This dual approach includes tabulating summary data, checking for heterogeneity, and evaluating the impact of study quality on results.Results: Our preliminary search yielded approximately 370 articles searching title and abstract and about 1460 searching full text. After rigorous screening and quality assessment, the final selection will provide a nuanced understanding of the relationship between religiosity and gambling. We anticipate revealing the multifaceted roles of religiosity, including protective and risk factors across different populations.