Numerous empirical studies have been carried out to explore factors of online health management continuance. However, results were not unified. We thus conducted a meta-analysis to identify influential factors and potential moderators. A systematic literature search was performed in nine databases (PubMed, Web of Science, the Cochrane Library, Ovid of JBI, CINAHL, Embase, CNKI, VIP, and CBM) published up to December 2020 in the English or Chinese language. Meta-analysis of combined effect size, heterogeneity, moderator analysis, publication bias assessment, and inter-rater reliability was conducted. Totally 41 studies and 12 pairwise relationships were identified. Confirmation, perceived usefulness, satisfaction, information quality, service quality, perceived ease of use, and trust were all critical predictors. Service type and age difference showed their moderating effects respectively. The perceived usefulness was more noteworthy in medical service than health and fitness service. The trust was more noteworthy in young adults. The results confirmed the validity and robustness of the Expectation Confirmation Model, Information Systems Success Model, and trust theory in online health management continuance. Moderators included but are not limited to age difference and service type. The elderly research in the healthcare context and other analytical methods such as qualitative comparative analysis should be applied in the future.