This study addresses the vibration problems in high-speed long-shaft rotor system of an aerial UAV by developing a computational model that incorporates various forms of bearing support and damping. Using Ansys Workbench, the effects of bearing support forms and bearing damping on the critical speed of the rotor system are analyzed. Results indicate that the critical speed is significantly higher with rigid support than with flexible support. When rigid support is combined with bearing damping, the critical speed decreases with the increase of damping, and the influence of bearing damping decreases in higher-order modes. Additionally, the harmonic responses of the system are consistent across different positions, with the response amplitude increasing as the unbalanced load rises. Furthermore, the response amplitude shows an upward trend with increased damping.