Over the years, there has been a growing interest in the field of power harvesting technologies for low-power electronic devices, such as wireless sensor networks and biomedical sensor applications. Of all possible energy sources, the mechanical vibrations have been considered a potential choice for power harvesting in a wide variety of applications. This paper presents the development of a piezoelectric MEMS generator which has the ability to scavenge mechanical energy of ambient vibrations from their surroundings and transform it into electrical energy that can be used in energy storage applications. The piezoelectric MEMS generator comprises a beam structure based on the silicon wafer, and the digitate electrode placed in between the lead zirconate titanate (Pb(Zr,Ti) O3, PZT) material and the beam structure, to transform mechanical strain energy into electrical charge with using the d33 mode of PZT. An optional proof mass can be built at the tip of the beam, to adjust the structure resonant frequency of the piezoelectric MEMS generator, for most adaptable frequency matching to the ambient vibration of its surroundings. A theoretical model is also presented to investigate the relations between the charge generation ability and the design parameters of the piezoelectric MEMS generator. To improve the piezoelectric MEMS generator fabrication process, a self-made PZT deposition chamber which could deposit PZT thin film up to tens micron in minutes was used to deposit the piezoelectric layer on the beam structure of the piezoelectric MEMS generator.