Aiming at the problems of large damping,narrow band,complex structure and cumbersome installation of the omidirectional vibration energy harvesting device,the design of the multidirectional vibration energy harvesting device with the energy harvesting module replaceable is optimized in this paper.In the structure,the device realizes the transformation of the conventional energy harvesting device from a single unitary structure to a modular assembly;in performance,the material size is determined by the theoretical simulation and the performance is tested experimentally.Compared with the conventional device,the maximum peak voltage of the newly designed one has been increased by about 11 times and the maximum output power is up to 28.75 μm.