Green innovation plays a critical role in facilitating firms to achieve sustainable development. This study aims to investigate how global diversification affects green innovation. Existing literature suggests that global diversification can have both positive and negative effects on firms' engagement in green innovation. While it can increase firms' pressure and ability to participate in green innovation activities, thereby promoting their green innovation efforts, it can, however, be utilized to evade environmental responsibility, thereby hindering their green innovation efforts. In an empirical analysis focusing on a sample of Chinese multinational corporations (MNCs) from 2008 to 2020, MNCs' global diversification is found to affect their green innovation significantly and positively. Moreover, the positive effect of global diversification on green innovation is enhanced by factors, such as the host country's institutional quality, state ownership, and the CEO's academic experience. The findings suggest that global diversification can facilitate Chinese MNCs' engagement in green innovation activities rather than being utilized to evade environmental responsibility. Furthermore, the results reveal that the positive effect of global diversification on green innovation depends on the external and internal environments in which MNCs operate. Overall, this study provides new insight into the determinants of corporate green innovation in emerging market MNCs.