The experimental heat pump two-effect direct contact membrane distillation system was developed, and its performance was alsostudied systematically. The results showed that the device could concentrate thermal-sensible liquid under low temperature at atmospheric pressure and run under setting conditions by regulating the auxiliary cooler. The membrane flux and thermal efficiency could be greatly increased with the increasing of material temperature. Under the influence of the combined effect of the membrane component thermal efficiency and the heat pump coefficient, the gained output ratio could achieve 1.58 at 66 ℃.