Smooth guiding through the inside of a body cavity is carried out by a magnetic field applied from the outside of the body. The provided capsule medical device (1) includes a bio-information detecting device (5) for detecting bio information of the inside of a body cavity a magnet (12) for receiving a guidance magnetic field applied from outside the body and generating a driving force a coil (7) for receiving a position-detection magnetic field applied from outside the body and generating a position-detection signal a filter device (8), connected to the coil (7), for attenuating an induction signal component which is generated by the guidance magnetic field incident on the coil (7) and a wireless transmission device (10) for externally transmitting the position-detection signal which has passed through the filter device (8) and the bio information which has been detected by the bio-information detecting device (5).