Exhaust heat recovery system includes a conveying device for circulating a first refrigerant, heat supply for supplying the exhaust heat recovery heat exchanger for recovering waste heat from the outside of the system, the exhaust heat to the outside of the system and the heat exchanger to the outside of the system a heat exchanger, and exhaust heat exchanger for discharging excess heat in the system and outside the system and the heat exchanger from the system, the compressor, the first heat exchanger, expansion device, sequentially piping second heat exchanger in connected, and the auxiliary heat exchanger the second refrigerant circulates, comprising a heat recovery heat exchanger, the transport device, the first heat exchanger, the exhaust heat exchanger, the second heat exchanger, heat supply heat exchanger, but are connected by sequentially piping, a heat recovery system first refrigerant circulates, the auxiliary heat exchanger is provided with the controller, the flow through the outlet side of the second heat exchanger temperature in the first refrigerant is greater than the upper limit of the set temperature range, as the temperature of the first refrigerant flowing into the exhaust heat exchanger is increased, the compressor And it controls the throttle amount of the rolling speed and the throttle device.