Abstract: Soil samples collected from a pesticide-contaminated site in Beijing were treated with thermal desorption to determine the optimum temperature to remove DDTs and investigate the thermal desorption kinetics of DDTs from soil. Meanwhile, the effect of soil moisture on removal efficiency was investigated. Results indicated that thermal desorption could effectively remove DDTs from the soil. The removal efficiency reached 99%, when thermal desorption temperature was 340℃. The residue of concentration ∑DDTs in the soil was 0.598mg/kg, which meets the standard of soil quality assessment for exhibition sites in China (1.0mg/kg). The removal efficiency did not change much when the temperature gradually increased. The thermal desorption kinetics of ∑DDTs in the soil was well interpreted with the second-grade rate equation, which suggested that desorption rate was much impacted by the residue concentration of ∑DDTs. In another word, the thermal desorption rate would greatly decreased during this process. The removal efficiency of ∑DDTs was slightly affected by the moisture in soil. When the proportion of water in the soil was over than 16%, the removal efficiency of p,p-DDE obviously decreased, while those of other components changed not significantly.