Abstract: The evaluation of the carrying capacity of resources and environment and the suitability of national territory space development (hereinafter referred to as the 'double evaluations') are the basic basis for optimizing the pattern of national territorial space development and protection, and an important foundation for compiling national territorial spatial planning. The mountainous area has special natural environment and resource conditions, and the 'double evaluation' technical methods for such special areas are less concerned. To this end, the study summarizes the technical methods of 'double evaluations' guidelines at the national level and in some provinces firstly. On this basis, from the aspects of adjusting the evaluation elements according to the important influencing factors, highlighting the characteristics and changing the evaluation index, and determining evaluation index threshold according to the current situation, the improved technology method of 'double evaluation' in central counties combining the particularity of mountainous areas is proposed. Then Badong County, Hubei Province is taken as an example to conduct applied research. It is expected to provide a certain reference for the practice of 'double evaluations' at the county scale in mountainous areas, and better serve the national territorial space planning and ecological civilization construction.