Recently, materials and locomotion control methods of micro robot have been developed for applying to the biomedical application. Especially, many researches of biomimetics locomotion and magnetic actuators have been introduced. In this paper, we introduced methodology of dynamic actuation of the flexible magnetic actuator so as to drive micro robot. Proposed methodology presents both static motion and dynamic motion by correlation between the magnetic moment and the rotating magnetic field. This method can provide much more active movement than the general control method of ac and dc magnetic field. Various actuations of the flexible magnetic actuator are applied to new swimming method of fish-like micro robot and locomotion of inchworm-like micro robot. Also, the flexible magnetic actuator based the micro robots have not only advantage of the dynamic actuation but also advantage of wireless control and no inserted battery.