Abstract: County-level urban-rural integration is an essential approach to systematically reorganize territorial labor division and improve comprehensive development efficiency, and also provides important underpinning for guiding small towns to exert their comparative advantages. Taking Southwest China as the research scope, this paper constructs an evaluation framework of 'foundation-dynamics-outcome'. By adopting the combined weighting method and obstacle degree analysis model, it quantitatively evaluates the urban-rural integration level of 400 counties in Sichuan, Guizhou and Yunnan provinces, identifies key restrictive factors, and explores their typological differentiation characteristics. The results show that the overall urban-rural integration level in the study area presents an upward trend from a low starting level, accompanied by prominent structural imbalance: the foundation and dynamics dimensions obviously lag behind the outcome dimension, and the spatial distribution shows an evident core-periphery gradient pattern. Restrictive factors are mainly concentrated in the foundation and dynamics dimensions, which constitute the core bottlenecks restricting high-quality development at this stage. Based on the cross-classification of integration level and obstacle intensity, county types present spatial differentiation features of central agglomeration, corridor attachment and terrain restriction. Severely underdeveloped counties are predominantly distributed in peripheral mountainous areas, accounting for 42.50% of the total and being deeply trapped by topographical constraints. Transitional and development-restricted counties show zonal distribution along transportation corridors. A small number of counties with prominent developmental contradictions face the risk of decoupling between growth scale and development quality. This study argues that the outcome-dominated development model tends to mask the deficiencies of endogenous driving forces. It is necessary to optimize the development logic and smooth the systemic circulation of county-level urban-rural integration.