Purpose: This study aimed to examine effect sizes of leadership styles of nursing managers on turnover intention of hospital nurses. Methods: A systematic review and meta-analysis were conducted in accordance with the PRISMA and MOOSE guidelines. Participants were nurses working in hospitals. The intervention involved nursing managers’ leadership styles; the outcome assessed was nurses’ turnover in-tention. This was an observational study design. Eleven databases were searched to obtain articles published in Korean or English. Of the 14,428 articles reviewed, 21 were included in systematic review and meta-analysis. Comprehensive Meta-Analysis and R software programs were used. Results: The total effect size r (ESr) was - 0.25 (95% confidence interval: - 0.29 to - 0.20). Effect sizes of each leadership style on turnover intention were as follows: ethical leadership (ESr = - 0.34), transformational leadership (ESr = - 0.28), authentic leader-ship (ESr = - 0.23), transactional leadership (ESr = - 0.21), and passive avoidant leadership (ESr = 0.13). Ethical leadership was the most effective style in decreasing turnover intention of hospital nurses. Conclusion: Positive leadership styles of nurse managers effectively de-crease turnover intention of hospital nurses, and negative leadership styles of nurse managers effectively increase turnover intention of hospital nurses. The ethical leadership style is the most effective in decreasing turnover intention of hospital nurses; however, it requires careful interpretation as its effects are reported by only two studies. This study contributes to addressing the high turnover rate of hospi-tal nurses and developing positive leadership styles of nurse managers in hospital settings.