The study investigates the impact of corporate social responsibility (CSR) on environmental performance (EP) within Chinese SMEs, utilizing a resource-based view framework. Additionally, it examines the mediating role of green transformational leadership (GTL). Data from 524 respondents were analyzed using PLS-SEM. Results reveal significant influences of CSR dimensions (environment, employees, customers, and community) on environmental performance, indicating that environmentally focused CSR practices contribute to resource efficiency and ecosystem preservation. Moreover, GTL mediates these relationships, suggesting that employees are more inclined towards pro-environmental behaviors when their employer demonstrates a commitment to sustainability. Finally, this study provides theoretical and practical insights into CSR, GTL, and EP in Chinese SMEs, along with identified limitations and suggestions for future research.