The enhanced greenhouse gas effect is expected to cause high temperature increase globally, and this would lead to an increase in precipitation in some regions while other regions would probably experience reduction in precipitation. The impact of expected climate change will affect almost all the sectors of human endeavor, among which, water resources is the most direct and important sector. North-eastern China is scarce in water resources, while the region is main food source area of China as well. Climate change could probably aggravate the severe situation of shortage in water resources; in further, bring adverse effect on food security of China. The major purpose of the paper is to identify the contributions of human activity and climate change to historical changes in recorded runoff for Liaohe River basin, which is one of the major rivers in China, and exploit hydrological characteristics of Tieling station in response to climate change. Snowmelt-based water balance model (SWBM model) is employed in the study. Results indicate that recorded runoff at Tieling hydrometric station has been decreasing since the late 1960s, especially in the periods from 1966-1984 and 2001-2008, annual runoffs in the two periods decreased by 63.9% and 75.3% respectively comparing to 1951-1965. SWBM model can naturalize monthly runoff of Liaohe River basin with high accuracy. Nash-Sutcliffe coefficients in both calibration period and verification period for the 4 typical catchments are all above 65% while relative errors are less than 3.0%. Human activity plays main role in runoff reduction. During 1966-2008, annual recorded runoff decreased by 54.2% as comparing to 1951-1965, among which, human-induced runoff reduction is about 36.5%, and climate change induced runoff reduction is 17.7%. Increase in precipitation could put higher effect on stream flow than decrease in precipitation does, while soil moisture is more sensitive to precipitation reduction than to precipitation increase. Under the scenario of 10% increase in precipitation and no change in temperature, annual runoff and average soil moisture would increase by 22.4% and 6.5% respectively. If there were no change in precipitation, while temperature increased 1 degree, runoff and soil moisture would decrease by 5.5% and 7.3% respectively. Aridification of climate will extremely be not conducive to sustainable utilization of water resources and agricultural production for North-eastern China.