As new technologies emerge, such as digital technology, alternative technologies faced by environmental governance become increasingly widespread. This study utilizes the case of “Broadband China” to examine the influence of digital infrastructure on environmental performance. A difference-in-difference model is employed in this study, utilizing a panel dataset encompassing Chinese cities throughout the period of 2006 to 2019, in order to establish causal inference. The findings indicate that digital infrastructure can greatly enhance environmental performance, and a set of robustness tests support this finding. The mechanism test reveals that digital infrastructure development promotes internet development, boosts green innovation, and stimulates market vitality. Heterogeneity analysis suggests that the implementation of digital infrastructure improves environmental performance in China’s eastern, southern, and northern cities, as well as in non-industrial and large cities. Digital infrastructure mainly promotes green technological progress rather than green technological efficiency. This study provides reference to intensify digital economy-enabled green development.