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The statistical analysis of monthly rainfall data from 11 observation stations in Southeastern Shanxi Province from March to August, 1960 to 2000 is made. The spring and summer droughts are divided into 5 grades according to the number of droughts, the months that the droughts occurred, drought extent, etc. , to study the occurrence regularities of droughts. It is found that the southeastern Shanxi Province is an area that droughts strikes frequently. The precipitation forecast equations are devised by means of the optimum subset regression method, and the forecasting results appear promising. Based on the equations, the key factor impacting rainfall in the Southeastern Shanxi Province are identified preliminarily.