Application of active vibration control system based on piezoelectric elements in real-world structures is limited by its requirement for complicated signal processing system and bulky energy supply system;the passive vibration control system is also difficult to implement its system paramenters of inductance.Moreover,the resistances in this system are sensitive to environment,so that it needs large inductance to control low frequency vibration. In order to overcome these drawbacks, a new method of semi-active vibration control based on a technique of synchronized switch damping has been developed recently. By using the processor of TMS320F2812 and the logic switch control algorithm,the polarity of the voltage on a piezoelectric element embedded in cantilever composite beam can overturn at proper time, so that the vibration controlling effect is achieved due to the opposite directions of the voltage-induced force and the strain rate. The experimental results show that the first mode of the cantilever beam can reduce by 3.164 1 dB.