Abstract: Based on the actual monitoring data, the water supply service and its value of Liaohe Conservation Area were analyzed from two aspects in terms of water quantity and water quality from 2013 to 2016. The results showed that the water supply service of Liaohe Conservation Area witnessed a series of fluctuation. The water quantity, excessive pollution equivalent and water supply service value showed a similar trend of decrease followed by increase. During 2013 to 2016, the excessive pollution equivalent of each monitoring section was positive for each year, which meant that the water environment quality of each monitoring section had reached the target assessment requirements of Class Ⅳ of Environmental Quality Standards for Surface Water (GB 3838-2002). As for individual water monitoring sections, the Fudedian section had the lowest values of water quantity, excessive pollution equivalent and water supply service value, while those of the Mahushan section were the highest. The period of 2013 to 2016 witnessed a dramatically changing trend in the value of monthly water supply service and water supply service per unit water resource quantity in Liaohe Conservation Area; and the two change progresses were of significant differences. On the basis of monthly assessment analysis result of the Fudedian and Liujianfang section, a similar trend was found in the monthly excessive pollution equivalent and water quantity changes during the period of 2013 to 2016, but many differences were presented in the annual average value of monthly water supply service and water supply service of per unit water resource.