The utility model discloses a plasticizer reaction system which comprises a reaction tank system, a treating tank system and a vacuumizing device, wherein the vacuumizing device is connected with an outlet pipeline of a first heat exchanger; a first recycling tank and a second recycling tank of the reaction tank system are connected with each other through a pipeline; a second solenoid valve is mounted on the pipeline between the first recycling tank and the second recycling tank; a reaction tank of the reaction tank system is connected with a treating tank of the treating tank system through a pipeline; a second liquid flow pump and a third solenoid valve are mounted on the pipeline between the reaction tank and the treating tank. According to the plasticizer reaction system, the first recycling tank and a receiving tank in the reaction tank system are serially connected with the second recycling tank in the treating tank system, and materials of the reaction tank in the reaction tank system can be directly transferred to the treating tank in the treating tank system for treatment without influencing work of the reaction tank system and the treating tank system, so that the occupied time of the reaction tank in the reaction tank system can be shortened, then the batch time can be shortened, and the purposes of energy conservation and emission reduction are achieved.