Accurate estimation of the impact of urban form on carbon emissions of residents (CER) is a crucial prerequisite for China to adopt effective low-carbon spatial planning strategies and achieve the carbon peak and neutrality goals (hereafter “dual carbon” goals). However, as the most basic governmental unit and the new energy consumer in China, counties have rarely been concerned, and the relationship between their urban form and the CER is still limitedly understood.This paper seeks to investigate how urban form influences the CER by taking the 90 counties in the Yangtze River Delta of China as a case study. First, considering the features of the county's urban form and residents' energy consumption, this study focused on analyzing the urban form of the main center and the overall urban form composed of the main center and surrounding towns. Second, based on the needs of sustainable development at county level and the framework of China's territorial spatial planning, this study defined urban form in two dimensions: geometric-aspect urban form and built environment-aspect urban form. Finally, the relationships between urban form and the CER were modelled using partial least squares structural equation model (PLS-SEM). Results reveal that (1) the geometric-aspect urban form variables (scale, compactness, spatial structures, and shape) exert a direct influence on the CER.Controlling the urban development boundary, increasing compactness of themain center, developing in the direction of multiple centers, and minimizing the complexity and narrowness of theshape of the main center positively impact the CER. (2) For the built environment-aspect urban form variables, improving the accessibility of public service facilities and green space coverage is beneficial for counties to reduce the CER, and currently improving road traffic status and energy infrastructurehas a significant contribution to the growth of the CER.(3) The geometric characteristics of urban form indirectly affect the CER by influencing the built environment characteristics of urban form. Road traffic, greening spaces, public service facilities, and energy infrastructureare influential intermediaries. This study identifies the intricate correlation between the county's urban form and the CER, providing a scientific foundation for the formulation of policies aimed at optimizing urban form and achieving “dual carbon” goals.