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Based on the positive piezoelectric effect of piezoelectric ceramic(PZT), an energy harvesting device with cantilever beam is designed for the single pressing energy harvesting, which can be used for wireless switches and so on. The mathematical analysis of the response of PZT cantilever beam is carried out on the condition of single pressing. Through comparison of the performances, a cantilever beam is made of the selected P-81 piezoelectric plates which are superimposed on the both sides of the copper alloy sheet. Finite element analysis shows that the double piezoelectric plates connected in parallel can export higher power than that connected in series. However, the natural frequency has no relation with their connecting forms. It indicates that the connecting forms of the double piezoelectric plates have no effect on its strain. The harvester is simulated and tested under the single pressing condition with 10 kΩ resistance load. The calculated and tested maximum instantaneous powers are 28.93 mW and 27.46 mW, respectively. The energy harvesting circuit is designed according to the high impedance characteristic of the PZT at low frequency. A threshold switch circuit is used to control the discharge voltage. The experimental results show that the output electric energy of the energy harvesting circuit can reach 5.05 mJ. The energy can meet the requirements of driving LED, RF transmitter and so on.