This study explores the level of urban-rural integration development and its driving factors in the hilly and mountainous areas of Nanchong City，Sichuan Province， aiming to provide a decision-making basis for the balanced and high-quality development of urban and rural areas in the region. The entropy method， global spatial autocorrelation analysis， and spatial hotspot analysis were comprehensively adopted to analyze the spatio-temporal characteristics of the urban-rural integration development level in Nanchong City from 2008 to 2023， and an econometric model was constructed to identify its driving factors. The results show that： （1） Temporally， the urban-rural integration development level of Nanchong City presented a non-linear fluctuating upward trend from 2008 to 2023， and the integration level of all dimensions showed a fluctuating growth trend. （2） Spatially， the urban-rural integration development level of all districts （cities and counties） in Nanchong City formed a spatial differentiation characteristic of gradient decrease from Shunqing District， the main urban core， to the surrounding districts （cities and counties）. Meanwhile， the spatial agglomeration of cold and hot spots was significant， with the number of hot spot agglomeration areas decreasing and that of cold spot agglomeration areas changing in a steady fluctuation. （3） The urban-rural integration development of Nanchong City was mainly affected by the comprehensive interaction of multiple factors such as regional natural endowment conditions， government regulation factors and market mechanisms. Based on the above results， countermeasures and suggestions are put forward， including deepening the coordinated development of urban and rural economy based on the advantages of natural endowments， strengthening government macro-control to rationally allocate urban and rural public resources， and optimizing the market regulation mechanism to activate the value of rural resource elements.