The invention relates to a underwater robot control method of a rotatable rudder propeller. By using the method, five-degree-of-freedom motion control of an AUV is realized. The method comprises speed control, course control and vertical plane control. The speed control comprises speed open-loop control and speed closed-loop control. In the speed open-loop control, speed feedback is not considered and an axial thrust of the propeller is directly output and controlled. In the speed closed-loop control, the speed feedback is introduced into a speed controller. The course control is variable structure course control. The vertical plane control is divided into high maneuvering control and low maneuvering control. When a distance between a underwater robot and a target position is greater than a set value, the high maneuvering control is adopted; otherwise, the low maneuvering control is adopted. Compared to a traditional control method, the method of the invention possesses better robustness and is suitable for changes of an extraneous environment, and through using the method of the invention, a control capability of the AUV is increased. The method can be transplanted conveniently and can be suitable for various robots.