The invention discloses a device for accurately controlling an pickling roller, and aims at providing the device for accurately controlling the pickling roller, which can effectively control consistency of pole plate lead plaster density, pole plate thickness and pole plate weight, and improve consistency of single accumulator parameters. The device comprises a rack, a pressure adjustment device, a balanced roller support device, a pole plate conveyor belt, a pickling roller positioned above the pole plate conveyor belt, and a support roller positioned under the pole plate conveyor belt. The pickling roller comprises a roll shaft and a roller rotationally arranged on the roll shaft. The balanced roller support device comprises two support mechanisms. Each support mechanism comprises a vertical support cylinder arranged on the rack, a support piston arranged in the vertical support cylinder in a sliding manner and a vertical support rod arranged on the lower end face of the support piston. The lower end of the vertical support rod of one support mechanism is connected with one end of the roll shaft, while the lower end of the vertical support rod of the other support mechanism is connected with the other end of the roll shaft.