The utility model discloses a desulfurized gypsum ordinary pressure salt solution legal system is equipped with reaction unit of high strength gypsum, the cauldron body including the tube -shape, the cauldron body for bilayer structure in order to form hollow intermediate layer, has filled heat transfer medium in the intermediate layer and be equipped with the heating rod, the upper portion of cauldron body circumference side is equipped with filling runner and gas -exhausting flow path, filling runner and gas -exhausting flow path all are linked together with the intermediate layer, the cauldron is personally experienced sth. Part of the body lower part to the side of the circumference and is equipped with water discharge channel, water discharge channel is linked together with the inside of the cauldron body, and the bottom of the cauldron body is equipped with the temperature sensor who is used for detecting the internal temperature of cauldron, the kettle cover is installed to the upper end of the cauldron body, is equipped with on the kettle cover to throw the material pore, and the center department of kettle cover is fixed with the motor, and the output shaft of motor has stirring wing and drive stirring wing to rotate. The utility model discloses be equipped with the high strength gypsum in -process in ordinary pressure salt solution legal system, but the internal reaction condition of stable control cauldron, but the free water of rapid removal behind the desulfurized gypsum emergence dehydration reduces the emergence of secondary aquation, has improved product quality.