Using panel data from Chinese prefecture-level cities from 2005 to 2020，this study employs the pilot policy of universal telecommunications service as a proxy variable for rural digital infrastructure and utilizes a multi-period Difference-in-Differences （DID） approach to examine the impact of rural digital infrastructure on the urban–rural income gap.The research finds that rural digital infrastructure significantly narrows the income gap between urban and rural areas.After the implementation of the ’Universal Telecommunications Service’pilot policy，the Theil index and urban-rural income ratio in the pilot regions decreased on average by 0.0061 and 0.0863 units，respectively.Mechanism analysis indicates that rural digital infrastructure primarily reduces the income gap by promoting the flow of labor from rural to urban areas.Heterogeneity analysis shows that the policy effects are more pronounced in regions with weak talent cultivation capabilities，as well as in western and non-central cities.It is recommended to consolidate and expand the achievements of the universal telecommunications service pilot policy，enhance the standards of rural digital infrastructure，strengthen its integration with digital skills training for farmers and new urbanization initiatives and prioritize improvements in rural digital infrastructure in cities with low talent cultivation capabilities，western cities，and non-central cities.