Piezoelectric energy harvester has a good application prospect in the fields of mechanical,electronic and aerospace,and so on,because of its advantages of simple structure,high energy density,no electromagnetic interference,and the ability to collect vibration energy at a lower frequency.According to the dynamic design of improving generating efficiency for piezoelectric vibration energy harvester,the purpose is to study the electro-mechanical response characteristics of a piezoelectric cantilever beam under double excitation environments.According to the Euler-Bernoulli beam theory,the piezoelectric constitutive relation and the Kirchhoff’〖KG-*3〗s voltage laws,the electro-mechanical coupling dynamic model of double excited piezoelectric cantilever beam was established.Based on the Galerkin method and the modal superposition principle,the expression of electro-mechanical response of the piezoelectric cantilever beam was derived,and the model of root strain and output voltage was established.The electro-mechanical response characteristics of single or double excited piezoelectric cantilever beams were tested to verify the rationality of the theoretical derivation.Finally,the influence of phase on the output voltage of piezoelectric cantilever beam under double excitation was analyzed.The results show that the trends of strain amplitude frequency response of the piezoelectric cantilever beam under double excitations are consistent with the voltage response;under double excitations,the electro-mechanical amplitude frequency response of piezoelectric cantilever increases first,and decreases after reaching the extreme value at resonance frequency;the increased excitation amplitude decreases the stiffness and resonance frequency of the piezoelectric cantilever beam,and the maximum frequency drops to 15 Hz;the phase of the two excitation signals in the double excitations can affect the output voltage,which first decreases and then increases in a cycle.