The calibration device is used for automatically calibrating capacitances of a sensing capacitor at various frequency points in the touch screen, and comprising a calibration circuit and a comparison circuit. The calibration circuit is connected with the sensing capacitor and the comparison circuit to transmit a calibration excitation signal to the touch screen to start calibration operations at the various frequency points, and calibrate the sensing capacitor in the touch screen according to a comparison result from the comparison circuit; the comparison circuit is used for comparing a preset capacitance with the capacitance of the sensing capacitor at a current frequency point in the touch screen to obtain the comparison result, and feeding the comparison result back to the calibration circuit, and the calibration circuit calibrates the capacitance of the sensing capacitor to a capacitance that matches with the current frequency point.