Strict environmental regulations may change the behavioral decisions of rms. Based on the exogenous impact of the Chinese Central Government's inclusion of environmental performance in the assessment targets of municipal o cials in 2007, this study uses the difference-in-difference method to explore the impact of environmental regulations on employee income. We nd that (1) environmental regulations will signi cantly reduce the average wage level of employees in polluting industries and have no signi cant impact on nonpolluting industries. (2) This effect is more pronounced in eastern China, where environmental regulations are more stringent, and in areas where political promotion incentives are stronger. (3) Mechanistic analysis nds that environmental regulations will affect employee income by increasing costs and constraining nancing. ( 4) More importantly, we nd that the decline in the average wage level of rms is mainly due to the decline in the average wage level of ordinary employees, and the average wage level of management has not decreased signi cantly, which means that environmental regulations have expanded social income inequality. Our ndings contribute to a comprehensive understanding of the effectiveness of the implementation of environmental regulatory policies and economic cost issues.