Abstract: Calamity loss rate is the base for calculauon of insurance premium．The technique of “resolve-coordinate” of large system theory was used in classification of meteorological calamity degree of winter wheat，maize and cotton and regional division of calamity loss rate in Hebei Province．For the purposes of rationally and correctly determining regional calamity loss rate，regional division of the pereanial average calamity loss rate was used as the bastc control layer and the classification system of regional type and unit merging was used to conduct the regional division；while the perennial average calamity loss rate was utiliged as the calculation index to reflect the macro-and micro-space distribution of calamity loss．