Corporate social responsibility turned into a global sensation from the inception of the twenty-first century in the corporate world and grabbed immense engrossment from all stakeholders in their decision-making process. Capital structure and corporate governance practices are the well-mellowed facets of corporate finance literature. In this study, the moderating role of corporate social responsibility (CSR) between corporate governance and leverage of the US and Chinese listed firms has been established, with a further extension of analyzing the moderating role of CSR between corporate governance and leverage in high vs low leveraged firms and high CSR vs low CSR firms as the novelty of this study and has never been examined in both economies and globally. The data of 1989 Chinese-listed firms from 28 sectors of the economy and 6640 US-listed firms from 27 sectors of the economy has been taken from 2001 to 2019 and analyzed through fixed effect regression and system generalized method of moment (GMM). Results of the study reveal that CSR and corporate governance are negatively associated with the leverage of both Chinese and US firms. Moreover, the moderating role of CSR has established between corporate governance and leverage negative relationship. The moderating role of CSR in the relationship of leverage and corporate governance is established only in low-leveraged firms whereas it is insignificant in high-leveraged firms. System GMM confirms the signs and significance of the regression results; that is why regression results are robust and reliable, and there is no endogeneity problem in our model. The study also gives an insight for future research on high- and low-leveraged firms and firms with more CSR score than less CSR score with other dimensions such as firm performance and firm value variables.