A wideband vibration harvester based on piecewise linear system is proposed, which is mainly composed of the structure of diamagnetically stabilized levitation, induced coils and elastic films. The floating magnet is freely levitated between two pyrolytic graphite sheets without any external energy input. When a horizontal vibration excitation was applied to the vibration energy harvester, the floating magnet would oscillate between two pyrolysis graphite sheets, the floating magnet impacted to the elastic film with the increase of vibration intensity, which would cause the system stiffness to be segmented, the magnetic flux through the induced coils would change during the movement of the floating magnet, and the external vibration was converted into electrical energy. When the horizontal excitation amplitude is 5 mm, the operating bandwidth of the system reaches 3. 2 Hz, the maximum output voltage reaches 78 mV, and the maximum output power is 56. 3 μW. Under an excitation acceleration of 3 m/ s 2 , a maximum output voltage of 44 mV with the maximum power of 18 μW is obtained by the harvester, and the operating bandwidth of the system reaches 2 Hz.