The micro-level corporate social responsibility (CSR) literature has underscored the economic benefits of an organization's CSR investments, such as bolstering employees' organizational commitment and improving work performance. Yet, research on the potential influence of CSR in fostering socially oriented outcomes among employees has been rather scarce. This study aims to investigate the influence of CSR on employees' internal whistleblowing behaviors and the underlying mechanisms. A three-time-point survey was distributed across the service, manufacturing, construction, and financial insurance industries in Chinese enterprises. (...) The findings reveal that both internal and external CSR positively impact employees' internal whistleblowing behaviors through the mediating role of moral courage, with internal CSR demonstrating a stronger effect. Organizational loyalty positively moderates the mediating role of moral courage in the relationship between internal CSR/external CSR and internal whistleblowing behaviors. Theoretically, this study presents a pioneering endeavor in establishing the link between CSR and employees' internal whistleblowing behaviors, underscoring the significant role that employees' perceptions of CSR play in enhancing societal well-being and ethical governance. Besides contributing to the micro-level CSR literature, this study also provides practical insights for organizations seeking to leverage CSR as a tool for promoting employees' ethical conduct. (shrink)