Aimed at investigating the variable speed effect on hovering rotor aerodynamic performance, a numerical method based on the computational fluid dynamics has been established, and the scaled rotor model test has been carried out. Relations between the hovering performance of a hingeless rigid rotor and the rotating speed was studied. The results show that the rotor computational fluid dynamics method based on the moving-embedded grid technique and unsteady flow field solving method has a high accuracy. The error of hovering performance calculation is no larger than 6.84%. The model rotor test data is valid and has good repeatability. When the rotating speed decreases, the lift coefficient corresponding to the same collective pitch is smaller, while the lift coefficient corresponding to the inflection point of the figure of merit is larger. The smaller the lift force, the more obvious the power saved by the variable speed. More than 40% of the power required can be saved for a low lift case. It is demonstrated that a significant improvement in hovering aerodynamic performance can be achieved by changing the rotating speed.