In order to broaden the frequency band of traditional piezoelectric vibration energy harvester and improve the collection efficiency, this paper proposes a dual-cantilever piezo-magneto-elastic energy harvester (DCPEH). In order to facilitate the design analysis and parameter optimization of the structure, a theoretical model of lumped-parameters was established, and an experimental platform was constructed using aluminum alloy and piezoelectric fiber material MFC-8514-P2. The energy harvesting effect of the system was verified by experiments. The results show that the numerical simulation results are basically consistent with the experimental values within the error tolerance range. The proposed device can effectively optimize the energy harvesting performance. The upper beam bandwidth can be increased by 40%, and the peak amplitude can be increased by 19.6%. The other beam exhibits a double peak characteristic. Based on the simulation and experimental data, the characteristics of DCPEH are initially discussed.