This paper studied the characteristics of the bimorph piezoelectric vibrator for piezoelectric pump. By simulating the working conditions of the vibration in the pump, we constructed a dynamic model and derived the bending vibration equations of the piezoelectric vibrator under different support conditions. Then the analysis of finite element simulation is carried out for the equations, through which the vibration mode of the multi-order modal of the piezoelectric vibrator was acquired, and the relationship between the deformation deflection and peripheral support stiffness of the piezoelectric vibrator was analyzed. Finally, the deformation of the piezoelectric vibrator was tested. It is found that the test results are consistent with the conclusions of the finite element simulation, which provides a theoretical basis for the optimal design of the bimorph piezoelectric vibrator.