Abstract: In order to accurately simulate the variation characteristics of geothermal field in heat exchange zone,variation of heat transfer performance of the system and heat accumulation effect of ground source heat pump under different groundwater seepage conditions,the experimental site of Tongji University Eco-Park was taken as the research object,a numerical simulation model of three fields coupled with water,medium and heat is established by the theoretical analysis and numerical simulation. The results show that with the increase of seepage velocity of groundwater,the heat gradually shifts to the direction of groundwater flow. The diffusion migration amplitude of silt layer is smaller than that of fine sand layer,and fine sand layer is smaller than that of coarse sand layer. At the depth of 0-80 m,the heat accumulation of soil layer is obvious,and the heat accumulation of soil layer at the depth of 80-100 m is less. With the increase of groundwater seepage velocity,the heat transfer power per unit depth of buried tube heat exchanger increases gradually,and the relationship between them is linear. The heat transfer power increases by 0.53%,1.31% and 2.43% respectively when the groundwater seepage velocity is 1.33×10-4,6.30×10-4 and 1.27×10-3 m/d.