The utility model discloses an evaporimeter that boils of engine exhaust recycling, include by tail gas heat exchange area, fluorine lyons refrigerant heat exchange area, refrigerant import pipe and refrigerant outlet pipe, multiunit hot plate and with the fin that sets up in turn of hot plate, the hot plate penetrate go up the perforation after -fixing on mainboard and the lower mainboard, the condensation segment of hot plate is arranged in tail gas heat exchange area in, the evaporation zone of hot plate is arranged in in the refrigerant heat exchange area. The utility model discloses a tail gas heat exchange area and fluorine lyons refrigerant heat exchange area divide maybe two independent closed areas, though the product lost efficacy under extreme condition or life -cycle time in lost efficacy and result in freon to be revealed, can not get into cycle of engine tail region intra -area yet, therefore can avoid freon to take place to react because of pyrolysis and with the air, produce gaseous matter discharge atmosphere such as hypertoxic cyanogen fluoric acid, heavy damage and air pollution's phenomenon production.