A situation where a medical device is outside a region suitable for guidance control thereof can be easily coped with. Included are a medical device provided with a magnet a guiding unit (5X-1, 5X-2, 5Y-1, 5Y-2, 5Z-1, 5Z-2) that forms a control magnetic field for guidance control of the medical device, inside a prescribed control area a detection unit (7Y-1, 7Y-2) that detects positional information of the medical device and a computational unit that judges that the medical device has gone outside the control area on the basis of an output from the detection unit (7Y-1, 7Y-2) and calculates a direction for returning the medical device to the control area, wherein a signal-waveform calculating unit (21) stops forming the control magnetic field when the medical device is outside the control area.