Land use and climate changes are the important reasons for leads to the water resources change at a basin scale.This paper got a suitable model by calibrating distributed hydrological model SWAT (Soil and Water Assessment Tool)for Taohe River Basin.Take Taohe river in northwest China as an example,constructed scenarios based on comprehensive consideration of variation characteristics of Land use and climate changes.Then simulated the hydrological characteristics and discussed the hydrological response in different scenarios at basin scale.The results showed that:(1)After successful calibration verification,the correlation coefficient(R2),relative error(Re)and Nash-Suttcliffe coefficient(Ens)of SWAT model are 0.83,-8% and 0.68 respectively.It shows that the calibrated SWAT model can simulate the monthly flows well,and is thus applicable to the study of Taohe River Basin.(2)Compared with 1976-1995,water yield throughout this basin has increased by 1.30 mm due to climate change and decreased by 0.77 mm due to land use change. The effect of the land use change on hydrological characteristics is less than climate change.However,the land use change is anunneglectable factor in basin management.From the scenarios of extreme land use change,the water yield in forest,pasture and farmland are changed by 18.1% ,-7.4% and-10.1%respectively compared with that of the 1985land use scenarios.From the scenarios of climate change,the temperature changes are 2℃ ,1℃ ,-1℃ and 2℃ respectively when the precipitation is unchanged,and the changes in basin-wide water yield are-4.23% ,-2.56% ,3.08%and 6.70%,respectively.The precipitation changes are 20% ,10% ,-10% and-20%respectively when the temperature is unchanged,and the changes in basin-wide water yield are 56.32% ,30.88% ,-23.66% and-45.94%,respectively.(3)The interaction of land use and climate changes,the area of surface runoff increase mainly locates in Guanghe, Hezhen and Kangle county of the lower reaches of Taohe River,and in Luqu and Xiahe county of the upper reaches of Taohe River.The area of the surface runoff increase is about 39%in the total area.