In bone cell culturing environment, mechanical vibration has been utilized to study the effects of various frequency and amplitude conditions on the cells. In this study, a spreading single cell was modeled as a simple dome to investigate the dynamic properties of a cell in the culturing environment. The finite element modal analysis was applied to evaluate the natural frequency and mode shapes of a spreading bone cell. The variance of cell shapes and mechanical properties such as Young's modulus were utilized. Simulation results show that the range of the natural frequency for a spreading cell of various sizes (135x30, 100x40, 80x50, and 67x60 μm with 10 μm height) is 9.95-211.05 Hz and cell shapes do not affect the modal analysis results. However the natural frequency is increased proportionally to the increase in Young's modulus.