Based on the data of rainfall and evaporation from 6 observatories of Yongchang,Sunan,Tianzhu,Gulang,Wuwei and Minqin in the Shiyang River Basin from 1961 to 2000 and the data of river-flow from 9 hydrometric stations of Huangyanghe Reservoir,Zamusi,Nanying,Sigouzui,Gulang,Shagousi,Chajianmen,Dajingxia Reservoir and Hongyashan Reservoir from 1961 to 2000,the variety characteristics of hydrologic factors in the Shiyang River Basin were analyzed by using the method of analyzing the departure from the average and Kendall correlated analytical method.The results shows that there is uneven distribution of rainfall and evaporation in a year,but there is no large change among years.Nearly about 65% of the rainfall in whole the year concentrate from June to September,while about 54% of evaporation in the whole year concentrate from May to August..The distribution of river-flow in a year correspond with the rainfall,concentrating from June to September,which is about 58% of that in the whole year.The variety among years presents obvious decreasing trend,especially the inflow to the Hongyashan Reservoir.