Abstract: Considering the effect of groundwater seepage,a semi-analytical model of deep borehole heat exchanger is proposed based on moving line source model. A numerical model was established based on FLUENT software,and the numerical model,semi-analytical model and semi-analytical model ignoring groundwater seepage were compared under two boundary conditions of known inlet fluid temperature and total heat input rate. The results show that the semi-analytical model with the two boundary conditions has large errors in the early stage,but agrees well with the numerical model in the middle and late stage,and its accuracy is higher than that of the semianalytical model ignoring groundwater seepage,especially when the groundwater seepage velocity is high. The results show that the proposed semi-analytical model can be used to analyze the heat transfer of deep borehole heat exchanger with groundwater seepage.