The utility model relates to a self -circulation MVR heat pump evaporation system, including the pre -heater that preheats stoste, the heat exchanger who is connected with the pre -heater and the cyclone who is connected with heat exchanger, the export of pre -heater connects to the cyclone entry of cyclone lower part through the tube side of pipeline through heat exchanger, cyclone's well upper portion behind the filtering layer by the cyclone gas outlet connect to the import of roots's fan, the export of roots's fan connects to cyclone's top import through the shell side of pipeline through heat exchanger, the leakage fluid dram of heat exchanger shell side connect to the condensate case, the heat exchange line that the leakage fluid dram of condensate case passes through among the preheater discharges. The utility model discloses a roots's fan provides depressurized environment with the inside evacuation of equipment to reduce the stoste boiling point, reduce the energy consumption, utilize the air behind the circulation heating to give stoste heating among the heat exchanger before the concentrated operating mode, abandoned to external world steam and auxiliary electric heater's reliance.