The invention discloses an energy-saving reaction kettle with high-efficiency heat exchange function. The reaction kettle comprises a kettle body, and a transmission shaft inserted into the kettle body and driven by a first motor. Fixed stirring paddles and movable stirring paddles are arranged on the transmission shaft, which is provided with an annular recessed structure and a bearing platform.The reaction kettle further comprises a lifting plate which is driven by a driving mechanism and connected with the movable stirring paddles to drive the movable stirring paddles to move between the annular recessed structure and the bearing platform. A cooling coil is arranged in the kettle body; the top of the kettle body is provided with a feeding pipe, an exhaust pipe and a first thermometer;and the bottom of the kettle body is provided with a discharge pipe for installing a discharge valve and a second thermometer. The reaction kettle further comprises a controller and a pressure sensorchip. The first motor, the driving mechanism, the pressure sensor chip, the discharge valve and each thermometer are all connected to the controller. The reaction kettle of the invention can help promote the fluidity and heat transfer uniformity of a material and improve the heat exchange effect between the kettle and the cooling coil, and can also start corresponding movable stirring paddles according to the amount of the material to be fed. Thereby, the reaction kettle has achieved an energy-saving effect.