An object of the present invention is to readily initiate an operation of a capsule medical apparatus which is inserted into a subject and executes a predetermined function. In a capsule endoscope 3 according to the present invention, a reed switch 14 connected to a power supply unit and a function executing unit is arranged parallel to a direction of a longitudinal axis t of a capsule-like casing 16 in the substantially cylindrical capsule-like casing 16 of the capsule endoscope 3. A pair of movable electrodes of the reed switch 14 operates according to magnetic induction of a magnetic field of a magnet 6 applied substantially parallel to the direction t of the longitudinal axis of the capsule-like casing 16, and come into contact with each other. As a result, power supply from the power supply unit to the function executing unit is allowed.