Study on groundwater circulation law is the precondition of reasonable exploitation and utilization of groundwater resources. This paper selected the Jinghe River as research object to confirm the groundwater flow direction using groundwater simulation technology, divided the flow system into three circulatory systems, including local circulation system, middle circulation system and local circulation system. The depth and width of the three circulatory systems were obtained in the Jinghe River profile. The depths are respectively 20-160 m, 160-700m and 700-1000m, and widths are respectively 3-8 km, 8-34 km and 34-70 km. According to the velocity distribution characteristics, the flow velocity was divided into the strong runoff field with velocity＞0.01m/d, moderate runoff field with velocity of 0.005～0.01m/d and weak runoff field with velocity＜0.005m/d. The update time of groundwater flow in the various runoff fields were calculated. The results show that the update time of the strong runoff field is shorter than 4109 years, the moderate runoff field is between 4,109 and 24,657 years, and the weak runoff field is longer than 24,657 years.