This paper proposes a cableless in-piping magnetic actuator that exhibits a very high-speed locomotion into inner pipe of 8 mm. The cableless magnetic actuator is moved according to the vibration amplitude and resonance energy of a mass-spring system excited by using an electromagnetic force. The iron core size of the bobbin type electromagnet was roughly designed by computer simulation and then optimized experimentally. The proposed actuator incorporates an electrical inverter that directly transforms DC from button batteries into AC. The electrical DC-AC inverter incorporates a mass-spring system, a reed switch and a curved permanent magnet that switch under an electromagnetic force. The duty ratio is changed into this electrical inverter by changing the position of the curved magnet and the reed switch. Experimental result demonstrates that the cableless magnetic actuator was able to move horizontally at 471 m, and horizontal speed at 327 mm/s when Maxell SR621W silver-oxide button batteries were used.