Abstract: To address the lack of regional building earthquake damage data in Weining County, Guizhou Province, this paper focuses on the core requirements of building vulnerability assessment. Taking building structure type, construction age, economic development level, and regional climate condition as four core dimensions, the influence mechanisms and correlations of each dimension on building vulnerability are systematically analyzed. On this basis, the Analytic Hierarchy Process (AHP) is employed to quantitatively compare the regional similarities among Weining County, northeastern Yunnan, and southern Sichuan. The latter two regions, which are geographically adjacent to Weining County with similar climate and comparable economic development levels, are selected as reference areas.A similarity-based weighting evaluation system is established to quantitatively select the vulnerability matrix that best matches the actual conditions of Weining County. The findings provide critical data to support building vulnerability assessment and seismic risk evaluation in Weining, offer both theoretical and practical foundations for the development of local seismic disaster prevention plans and building retrofitting, and present a transferable methodological framework and implementation pathway for building vulnerability assessment in other regions lacking historical earthquake damage data.