The working principle of the harmonic oscillator is introduced. Using the soft of ANSYS,the solid model of harmonic oscillator mass is created by adopting the finite element method.Single crystal silicon is chosen as the material of mass of harmonic oscillator.The material attributes of modal is set and the modal is meshed by ways of smart meshing.Then a horizontal load is applied along with the X axis for the static analysis and modal analysis.The total displacement of physical model by static analysis is 0.236×10-19 μm.Only the fourth order of modal is analyzed by modal analysis.According to the vibration mode and the stress nephogram of total displacement,the twentieth order vibration mode frequency of physical models is 78 001 Hz and the total displacement is 0.122×10-6 μm.