In this study, we present an approach for micromechanical resonant accelerometer design, structural optimization and testing method of a kind of resonant accelerometer which is excited by the electrostatic force and detected by the change of capacitance. The structure parameters’ influence on capability parameters are analyzed by MATLAB and the mechanical and model analysis of structure are carried out by ANSYS, also, we optimized the structure parameters. Simulating results validates the design thought.