This study constructs a comprehensive and integrated enterprise internationalization (EI) index using data of Chinese A-share listed companies between 2009 and 2019 to explore the effect of environmental, social and corporate governance (ESG) performance on EI. The study finds that firms' ESG performance can facilitate internationalization, and the result hold after addressing endogeneity and robustness concerns. The mechanism test shows that cooperative research and development (R&D) is a channel through which the process of ESG performance promotes EI. These findings enrich the literature in ESG related fields and provide new insights for enterprises to accelerate the internationalization process.