This experiment aimed to investigate the bimorph piezoelectric vibrator of piezoelectric ceramic vibration feeder and propose the mechanical expression so as to lay a theoretical foundation for optimization design. Taking disk piezoelectric oscillator of spiral type piezoelectric vibration feeder as an example, the dynamic analysis was carried out on the disc-type double piezoelectric wafer, the vibration model and the dynamic equation were established for solving vibration force. Using Rayleigh Ritz method, the resonant frequency of the bending vibration of bimorph oscillator and the exciting force expressions were deduced under the simply supported boundary conditions. It was concluded that the maximum error appeared at 160 V, the error between the theoretical calculation and the experimental verification of data was about 10%, the error between the finite element analysis and the experiment validation data was about 5%. Through the experiment, it was concluded that, in practice, the input voltage of the piezoelectric layer and the deformation degree should be equally considered and the best power input should be selected to achieve maximum displacement of the double piezoelectric wafer.