Static and dynamic characteristic of carbon nanotube is analyzed by molecular dynamic simulation. Static analysis show that maximum deflection of carbon nanotube appears at 0.033nm distance from free end of cantilever. When the value of driving voltage is less, the flexibility is more important, then the stiffness increase with the voltage increasing, and the collapse structure or hole appear on carbon nanobute. Under low pressure condition, deflection difference on equi-increase of pressure between no damping and damping simulation is larger than that on high pressure. The results of forced vibration indicate that system response consist of transient and steady-state response. With steps of molecular dynamic simulation increasing, transient response disappears gradually, so system response includes only steady-state response, which is simple harmonic vibration with the same frequency as excitation force. These results are in accord with the classical vibration theory. Moreover they will provide theoretic foundation for designing of nanostructure device.