In the region of black soils,spring drought does great damage to wheat,but may not give anydamage to cultivated crops such as soybean and corn.Therefore.in years of spring drought,less wheat and more soybean and corn should be plantrd.Adoption of comprehensive agricultural technique including reasonable cultivation system of reserving soil water,correctly using soil water after removing crops,selection of good varieties and rltional fertilizing system,may also give a higher yield of wheat even in years of sprint drought.But,if we want to improve the water condition in black soils perfectly,we should increase the proportion of soybean and corn in the rotation system,and give up the cropping system of wheat-wheat-soybean.In this way,we could decrease the soil water consumption in the rotation system and establish a favorable and balanced water cycle in this soil region.