Although the nationwide poverty has been basically eliminated at present in China,the contiguous and concentrated distribution pattern of underdeveloped areas has not changed significantly. In the poverty- stricken areas, generally, resources and environmental conditions have more direct and obvious impacts on the local socio-economic structure. In this paper, firstly, we analyze the spatial coupling relationship between the distribution pattern of underdeveloped areas and the basic elements of resources and environment. The classification of constrained types of resource and environmental condition in national- level poverty counties shows that 456 poverty counties are restricted prominently by the resources and environment in China, accounting for 77% of all of the national-level poverty counties (592), and the proportions of resource- constrained types, environment- constrained types and comprehensive- constrained types are 33%, 23% and 21% respectively. Secondly, based on the case studies of Xiji-Haiyuan-Guyuan area of Ningxia Hui autonomous region and Nujiang Lisu autonomous prefecture of Yunnan province, the overall resources and environment carrying capacity in underdeveloped areas is proved to be relatively weak; the resource and environmental burden is chronically overloading; the response to changes among elements is sensitive; and the potential to enhance capacity is greatly limited. Moreover, the recovery cost is tremendous once the local carrying capacity is overloaded. The results show that these factors such as the mobility and migration of overloading population, the comprehensive renovation of regional eco-environment, the construction of large-scale infrastructure projects, the interaction among regional resource and environmental elements, and the emergency of natural disasters and tendency of global warming have significantly affected resources and environment carrying capacity in underdeveloped areas. Consequently, besides the water and land conditions, eco-environment, resources endowment and other traditional factors, the uncertain factors such as technological progress, institutional and policy arrangements should be taken into consideration in the establishment process of evaluation index system of resources and environment carrying capacity.