Based on panel data from 204 prefecture-level cities in China spanning from 2010 to 2019, this study examines the low-carbon city pilot program as a quasi-natural experiment. The propensity score matching-double difference model (PSM-DID) is utilized to analyze the effects of the low-carbon city pilot policy on carbon emission intensity. The research findings found: Firstly, the low-carbon city pilot policy has significantly reduced the intensity of urban carbon emissions. Secondly, the primary factors contributing to the reduction in urban carbon emissions intensity due to the low-carbon city pilot policy include adjustments in industrial structure, energy consumption control, and advancements in green technology innovation. Thirdly, heterogeneity analysis indicates that the impacts of the low-carbon city pilot policy differ across various regions. Resource cities, eastern cities, as well as cities in the southeast and northwest regions, experience significant effects.