Abstract: Water from the Heilongtan spring group is one of the main sources for living, landscape and the service in the old town of Lijiang. In recent years, the amplitude of the spring group flows between wet and dry period is increasing. Seasonal or annual drought event is occurred when in drought or extreme drought years. Since August, 2011, the Heilongtan spring group’s flow has reduced significantly. The monthly average flow has reduced from 0.695 m3/s to 0.186 m3/s. And zero flow once occurred on January 21, 2012. On June 13, 2013, the spring group is still zero flow. In this paper, karst water system of the Heilongtan spring is analyzed. It is considered that the main reason of zero flow is less precipitation. While both of the ecologic environment destruction in the recharge area and the exploitation of groundwater also aggravates the setting off frequency of the Heilongtan spring. On this basis, some measures are put forward in the paper, such as improving the water conservation function of recharge area, strengthening the control and management of water resources, managing the water conservation district according to law strictly.