Based on panel data from 286 cities at the prefecture level and above in China spanning from 2010 to 2020 and utilizing the digital economy development objectives advanced by the “Broadband China” strategy in 2014 as a natural experiment, we employed the double-difference method to examine the impact of digital economy development on urban environmental pollution management and its underlying mechanisms. The study reveals that the “Broadband China” pilot policy significantly influences the level of environmental pollution control when compared to non-demonstration cities. This conclusion still holds after a series of robustness tests. The mechanism analysis demonstrates that the “Broadband China” pilot policy affects the level of environmental pollution control by enhancing regional innovation capacity and upgrading the industrial structure. Moreover, heterogeneity analysis indicates that the influence of the “Broadband China” pilot policy on environmental pollution control varies depending on location choice, city size, and degree of urbanization. Notably, the impact of constructing demonstration cities is particularly pronounced in the eastern region, larger cities, and areas with higher urbanization rates. This study holds significant implications for enhancing the urban ecological environment and achieving high-quality development.

The construction of new industrial-agricultural and urban–rural relations (IAUR) with coordinated development and shared prosperity is an inevitable requirement of the Chinese path to modernization. Based on the panel data of 275 prefecture-level cities and above in China from 2012 to 2023, we empirically verify the mechanism and spatial effects of the DE on the development of IAUR. The results show that: Firstly, the DE can effectively promote the development of IAUR, but there is a heterogeneous effect among cities with different geographic locations, administrative grades, and levels of development of the DE. Secondly, the promotional effect of DE on IAUR exhibits a non-linear pattern of increasing marginal returns, with digital financial inclusion (DFI) and the digital divide (DDI) serving as dual thresholds. Thirdly, the spatial spillover characteristics of the DE on the development of IAUR are obvious. Based on the above, policy recommendations are put forward, such as the widespread application of the DE, exploring differentiated development paths according to local conditions, and strengthening regional synergy and cooperation.