The utility model belongs to the technical field of curcumin production, concretely relates to a circulation reaction unit for curcumin preparation, including the cauldron body, cauldron body bottom is provided with the baffle of tube -shape, be provided with the catalyst piece in the middle of the baffle, catalyst piece top is provided with the stirring rod, the stirring rod lower extreme is provided with the stirring leaf, the cauldron body is stretched out to the stirring rod upper end, link to each other with the motor, the reactor comprises a kettle, the stirring leaf, be provided with the filtration pore on board lower portion's the wall, set up the partial baffle height of filtration pore is less than the catalyst piece half, the catalyst piece is the foaming body structure. The utility model has the advantages of simple structure and reasonable design, convenient to use, the catalyst that utilizes filtration pore and foaming body structure on baffle, the baffle forms stable liquid latus rectum at cauldron body center, guarantees the contact of reaction liquid and catalyst to effectively improve the efficiency of curcumin building -up reactions.