Social withdrawal (sometimes passive social withdrawal), the voluntary isolation of oneself from others, is becoming an increasingly severe problem for an ever-growing number of people. Although research has demonstrated factors that are associated with this phenomenon, a quantitative synthesis of the evidence is lacking. The current systematic review and meta-analysis examines the strength of the relationship between potential contributors and social withdrawal. It also investigates potential moderators of these relationships (e.g., gender, age, ethnicity, samples/populations, and study designs ). Based on the existing theoretical framework, a three-factor model involving individual, biological, and environmental factors is proposed, and possible contributors (e.g., risk or protective factors) of social withdrawal will be examined. Findings are expected to provide theoretical foundation for social withdrawal, which may inform future development of tailored prevention or interventions that target these respective factors