The invention relates to a strong human activity area water resource safety diagnosis space graph method based on county territory. The method comprises three main processes: county water resource quantity estimation, evaluation index establishment and scenario design and visualization. For the problems of lack of data information, difficult hydrological model parameter combination selection and complex natural-artificial binary water circulation mechanism and simulation and the like, the method, on the basis of theoretical basis of basin water balance, a Penman formula and a hydro-thermal coupling equilibrium equation based on Budyko hypothesis and the like, involves only one dimensionless parameter in the whole process, can carry out scientific and simplified estimation on strong human activity area county territory water resource quantity through a series of calculation steps by utilizing public meteorological data, drainage basin and administrative region water resource bulletin data and statistical yearbook data and the like, and diagnoses the water resource safety in the county territory and draws a water resource safety diagnosis space graph based on the established evaluation indexes and the designed situation combination.