To provide an exhaust heat recovery system having high exhaust heat recovery efficiency while reducing the power consumption of a hot water storage circuit circulation pump, and to provide a cogeneration system equipped therewith.

The exhaust heat recovery system comprises a hot water storage heat exchanger 3 having a primary side 3a where cooling water for a generating gas engine flows and a secondary side 3b where hot water flows, a first circuit in which the cooling water circulates between the generating gas engine and the hot water storage heat exchanger 3, a hot water storage tank 2 for storing the hot water, and a second circuit in which the hot water circulates between the hot water storage heat exchanger 3 and the hot water storage tank 2. It has a circulation thermistor 203 for detecting the temperature of the cooling water on the downstream side of the hot water storage heat exchanger 3 in the first circuit, a circulation pump 102 mounted in the second circuit for forcibly feeding the hot water, and a control means for controlling the flow amount of the circulation pump 102 in accordance with the temperature detected by the circulation thermistor 203.