Metamaterial is a type of composite material structure, in which a cell is repeated periodically with different materials integrated. Owing to the phenomenon that metamaterial structures can form a bandgap in spectrum and make the elastic wave propagation confined in it, they has attracted attentions in the fields of noise and vibration control. In this paper, we proposed a piezoelectric metamarerial, in which a piezoelectric material and a oscillate circuit form the cell. From the theoretical analysis, it is proved that the frequency band gap is generated. Furthermore, this kind of piezoelectric metamaterial is put on a cantilever beam to show the effect of vibration attenuation. The simulation investigation is carried out, including the studies on the vibration energy absorption, the influence of resistance and the vibration attenuation characteristic (combined with the voltage curve on PZT). The results focus on the significance of transmission and voltage, and show that the piezoelectric metamaterial is effective in vibration attenuation.