Taking the Jinqian river basin in the southern regions of Qinling mountains as typical area,the paper used the methods of the Mann-Kendall statistical method, regression analysis and double mass curve techniques to analyze the yearly variation characteristics of runoff and precipitation in the basin. In view of the rainfall yearly change, the relational model of rainfall and runoff is developed;Based on the precipitation-runoff empirical statistical model,it quantitatively assessed the impacts of precipitation change and human activities on runoff in the Jinqian river basin.The results indicate that the variation of runoff and precipitation in the Jinqian river basin are closely associated;the runoff coefficient presents a falling trend. In addition, an abrupt change point of precipitation and runoff took place in the period of 1988 to 1989;throigh the calculation by the model of precipitation and runoff relation,it got the result that both precipitation change and human activities have significant impacts on runoff in the Jinqian river. The decrease of runoff of Jinqian River mainly results from to human activities which account to 51.67%, while the rate of precipitation change accounts to 48.33%.