Abstract: In the report， in order to investigate the response of the runoff of Wanquan River to land use/cover change （LUCC） and climate change， the SWAT model was constructed， the different scenarios were set， the effects of LUCC and climate change on the runoff were quantitatively analyzed. The results showed that the model has a good applicability for the simulation of runoff in the upper reaches of the Wanquan River Basin， the correlation coefficient （R²） and Nash efficiency coefficient （Ens） of the validation period are both greater than 0.80. When the different land-use/land-cover scenarios were set， all artificial forest was converted to farmland， farmland was converted to natural forest， artificial forest was converted to natural forest， and the changes of monthly average runoff was 13.66%， -2.46%， and -9.74%， respectively， which suggested that the contribution of different land-use/land-cover to the increase of runoff is the highest， which is followed by farmlands， artificial forest， and natural forest. The analysis results from the different climate scenarios indicated that the change trend of monthly average runoff is directly proportional to the change of rainfall， however， which is inversely proportional to the change of temperature. The simulation of land-use/land-cover and climate showed that compared with that in 1990， the change of monthly average runoff brought by LUCC in 2018 increases by 1.32%； from 2006 to 2018， the change of average monthly runoff brought by the change of climate increases by 8.97%. Compared to the LUCC， the climate change is the main factor causing runoff changes.