Abstract: In this paper,the water saturation and residual water content of the backfill material in the boreholes were measured by the thermogravimetric method. The "graduated cylinder approach" was adopted to replace the ring knife method in this study. The matrix suction and water content were measured by the filter paper method. Based on the moisture content,the thermal characteristic parameters of the backfill material at different depths were calculated. The results showed that the greater the matrix suction,the lower the water content. Assuming that the highest point of the saturated zone is the water table,there is only 3.6% of water saturation at a distance of 100 m from the water table. Comparing the simulation results with the measured points,it shows that the measured results from the design method used matches the fitting results;compared with dry backfill material,the lower section of the borehole infiltrated by groundwater has a higher heat storage capacity near the water table,and the temperature change is relatively delayed. However,the thermal conductivity and thermal diffusion capacity are both affected. The heat storage and heat conduction capacity of the upper middle section is weakened,but the heat diffusion capacity is strengthened.