Piezoelectric shunt damping is a method to reduce structural vibration by shunting a piezoelectric element with an electrical circuit. This paper proposes a method to identify the physical parameters that are required to design piezoelectric shunt damping systems. Employing self-sensing actuator methodology, the proposed method requires no additional sensor or actuator other than a simple bridge circuit. The parameters can be identified from a transfer function simply by linear least squares method. To demonstrate the validity of the proposed method, the shunt damping of the steel plate with the piezoelectric ceramic is performed based on the identified parameters.