Abstract: The longlife batteries has been a pivotal technology in the wireless sensor networks.The energy in the chemical batteries is limited for long time work,so the replacement of depleted batteries will become impractical.This paper will present a new type of micro generator which utilizes electric-mechanical coupling character to harvest ambient vibration energy.The energy from vibration energy is the promising energy sources for micro-electric-mechanical system（MEMS）.The transform theory of piezoelectric generator and the primary analysis for the micro piezoelectric cantilever structure are present in the first parts.The Bulk and Surface silicon micromachining process is employed in the piezoelectric beam fabrication,such as wet anisotropic etching and RIE for silicon etching,Sol-Gel for PZT,platinum etching and so on.The key micro fabrication steps had been settled for the micro piezoelectric battery by trial and error.