An analytical model is derived for obtaining the dynamic performance of a thin curved composite piezoelectric beam with variable curvatures for the MEMS piezoelectric vibration energy harvester. The plane curved beam theory with rectangular section is employed to explore the bending and twisting coupling vibration characteristics. In order to satisfy the most available environmental frequencies, which are on the order of 1000Hz, the parameters of the spiraled composite beam bonded with piezoelectric on the surfaces are investigated to provide a method of how to design low resonance beams while keeping the compacting structural assembly. The results indicate the adoption of ANSYS® software to carry out the MEMS piezoelectric vibration energy harvester’s numerical simulation can improve the accuracy of the harvester designing and manufacturing consumedly. And the simulation data also provide a theory analysis foundation for the engineering, design and application of harvester.