Abstract: The hydrological response of eco-construction in a small watershed of Loess Hilly region was studied.The results show that the soil moisture increases along the down slope direction,and the spring flow increases with the soil water content increase.When runoff happens, the spring flow may increase 3～10 days afterwards.Eco-construction is caused the decrease in runoff modules in density rainfall fairs,but fully absorbs the rainfall in a long duration with low intensity rainfall fair,showing the eco-construction can be water bearing sustainability in the test region.