Considering the fact that Corporate Social Responsibility (CSR) is widely recognized for its positive impact on environmental performance, little research exists on its effect on the relationship between Green Human Resource Management (GHRM) and an Organization’s Environmental Performance (OEP). This study investigates how CSR affects GHRM and the OEP, along with its moderating effect. Data was collected from the Malaysian manufacturing industry and subsequently analyzed using the Partial Least Squares Structural Equation Modeling (PLS-SEM). The results revealed that GHRM and CSR positively and significantly affect the OEP. The study also revealed that CSR strengthens the existing relationship between GHRM and the OEP. Therefore, this study contributes to the existing literature by providing new scholarly evidence on the moderating effect of CSR on the GHRM-OEP nexus. The findings provide policymakers and the management of the manufacturing industry in Malaysia with fresh insights into the formulation of effective policies to promote CSR and GHRM practices within organizations.