The tagging system of the KEDR detector for the two-photon studies is briefly described. The procedure of the energy calibration of the system is considered. Two-photon events e+e- e+e- +μ+μ- selected with the central detector were employed to check the energy calibration and to measure the tagging efficiencies. The results obtained demonstrate that the achieved accuracy of the energy calibration is about 1%. To improve the accuracy to the level of 0.3% the upgrade of the calibration system is ongoing. The tagging efficiencies obtained with the simulation agree with the measured one within the error of the measurement.