This study examines the impact of human capital and globalization on carbon dioxide (CO2) emissions for a sample of 78 developing countries, from Asia, Africa, and Latin America and the Caribbean, over the period from 1990 to 2016. As opposed to the existing studies in the literature, this study considers three types of globalization namely economic, social, and political globalization. The econometric analysis involves the use of the two-stage least squares-generalized method of moment method to account for endogeneity issues. The findings, overall, indicate that human capital development decreases CO2 emissions in developing countries across all regions. In contrast, social globalization increases CO2 emissions in all developing countries. Moreover, the empirical results also reveal that political globalization boosts CO2 emissions in the Latin American and Caribbean region, but helps to curb CO2 emissions in Asia, Africa, and in overall panel. Additionally, economic globalization significantly reduces CO2 emissions in the Latin American and Caribbean region but increases CO2 emissions in Asia, Africa, and in overall panel countries. Furthermore, human capital and globalization (in all three forms) jointly boost CO2 emissions. Hence, in line with this major finding, we recommend that the globalization policies should also incorporate the human capital development agenda of the developing countries in order to comprehensively tackle the aggravation of CO2 emissions.