The regularities of the regional varieties of the crop ecologic factors and characteristics of the agricultural production in the Guan Zhong Plain are analyzed in this paper. Using the method of the fuzzy cluster we divided the plain into two subiegions first, that is, the easten semi-arid grain-cotton region and the westen semi-humid grain-oilcrop region. The boundary between them corresponds to the isopleth 1.50 cf the mean annual arid index. Further the result of subdivision is discussed in term of the i...