Geometric nonlinear behaviors of micro resonators have attracted extensive attention of MEMS(microelectro-mechanical systems) researchers,and MEMS transducers utilizing these behaviors have been widely researched and used due to the advantages of essentially digital output.Currently,the design of transducers with nonlinear behaviors is mainly performed by numerical method and rarely by system level design method.In this paper,the geometric nonlinear beam structure was modeled and established as a reusable library component by system level modeling and simulation method Mu PEN(multi port element network).A resonant accelerometer was constructed and simulated using this model together with Mu PEN reusable library.The AC(alternating current)analysis results of Mu PEN model agreed well with the results of architect model and the experiment results shown in the existing reference.Therefore,we are convinced that the beam component based on Mu PEN method is valid,and MEMS system level design method and related libraries can effectively model and simulate transducers with geometric nonlinear behaviors if appropriate system level components are available. Geometric nonlinear behaviors of micro resonators have attracted extensive attention of MEMS (microelectro-mechanical systems) researchers, and MEMS transducers utilizing these advantages have essentially researched and used due to the advantages of essentially digital output. Current, the design of transducers with nonlinear behaviors is mainly performed by numerical method and rarely by system level design method. This paper, the geometric nonlinear beam structure was modeled and established as a reusable library component by system level modeling and simulation method Mu PEN (multi port element network) .A resonant accelerometer was constructed and simulated using this model together with Mu PEN reusable library. The AC (alternating current) analysis results of Mu PEN model agreed well with the results of architect model and the experiment results shown in the existing reference.Therefore, we are convinced that the beam component based on Mu PEN method is valid, and MEMS system level design method and related libraries can effectively model and simulate transducers with geometric nonlinearities if appropriate system level components are available.