Implementations herein relate to a bistable piezoelectric cantilever vibration energy generator based on spherical composite structure with partial separation of different layers that includes a beam bracket and a shell. The shell is spherical, the bottom of the shell has a circular opening. The beam bracket and the shell are fixed to the base respectively. Vibration of the beam bracket can cause deformation of the piezoelectric cantilever beam, the piezoelectric cantilever beam generates electrical energy using the piezoelectric effect during deformation. The bistable piezoelectric cantilever vibration energy generator further includes twenty-five piezoelectric oscillator structures, and the lengths of the cantilever beam in the same layer are different such as to form a wide resonance frequency domain and to substantially increase power generation.