This paper presents the prototype of a new remote guiding device to find the accurate screw hole position for drilling and direction for locking in intramedullary nailing surgery. The device consists of three magnetic pins and an electrical conductive board. The three symmetrically placed magnetic pins can rotate freely and point to the permanent magnet inside the nail. The drilling position and screwing direction can be obtained by moving the device with those magnetic pins to align with the magnet in the nail. The alignment condition is indicated by a LED. When the device is not aligned with the magnet in the nail properly, either in position or direction, the pins then will contact with the board to trigger a light-emitting diode for alarming.