The invention provides an engine and an intelligent exhaust gas recycling (EGR) cooler thereof. The cooler comprises a shell with a sealed inner cavity, a valve block, a gas inlet pipe bundle, a first exhaust pipe bundle, a second exhaust pipe bundle and a driving part, wherein the sealed inner cavity is divided into a first inner cavity and a second inner cavity; the valve block is located in the second inner cavity and divides the second inner cavity into a first sub-cavity and a second sub-cavity; the gas inlet pipe bundle, the first exhaust pipe bundle and the second exhaust pipe bundle penetrate through the first inner cavity, the gas inlet pipe bundle and the first exhaust pipe bundle are led to the first sub-cavity, the second exhaust pipe bundle is led to the second sub-cavity, and the heat transfer coefficient of the second exhaust pipe bundle is larger than that of the first exhaust pipe bundle. When the temperature of exhaust gas entering the gas inlet pipe bundle is within a first temperature range, the driving part can drive the valve block to rotate in the first direction to enable the first sub-cavity and the second sub-cavity to be communicated; when the temperature of the exhaust gas entering the gas inlet pipe bundle is within a second temperature range, the driving part can drive the valve block to rotate in the second direction opposite to the first direction to enable the first sub-cavity and the second sub-cavity to be isolated. The problem that the temperature of exhaust gas exhausted from an existing EGR cooler has large fluctuation due to different working conditions of an engine is solved, and the performance of the engine and reliability of relevant parts are improved.