A capsule medical device guidance system 1 according to the present invention has a contact mode, in which a capsule endoscope 10 is brought into contact with a desired boundary surface in a plurality of boundary surfaces of a liquid in a subject, and an away mode, in which the capsule endoscope 10 is moved away from the desired boundary surface. When the contact mode is selected, an external control unit 4 controls a magnetic field generating unit 2 such that a total force in the liquid of a buoyant force of the capsule endoscope 10, a gravity of the capsule endoscope 10, or a magnetic attraction force is oriented toward the desired boundary surface side. When the away mode is selected, the external control unit 4 controls the magnetic field generating unit 2 such that total force in the liquid of a buoyant force of the capsule endoscope 10, a gravity of the capsule endoscope 10, or a magnetic attraction force is oriented toward a direction other than the direction oriented toward the desired boundary surface side.