A capsule medical system is provided with a capsule medical device to be inserted into a subject, at least one electrode pad having a plurality of receiving electrodes, a receiving electrode switching unit, a control unit for controlling operations of the receiving electrode switching unit, and a position detector. The capsule medical device has a biological information acquiring unit for acquiring biological information of the subject, and a transmitting unit for outputting the biological information from a transmitting electrode through a living body. At least one electrode pad detects the biological information by a plurality of receiving electrodes. The receiving electrode switching unit switches a pair of receiving electrodes among the plurality of receiving electrodes. The position detector detects a position of the capsule medical device inside the subject based on the biological information detected by the electrode pad, and position coordinate data of the plurality of receiving electrodes.