A capsule medical device guidance system (1; 201; 301), comprising: a capsule medical device configured to be introduced into a body cavity of a subject and to float in a liquid introduced into the body cavity, the capsule medical device including an imaging unit (11A, 11B) that is configured to capture an in-vivo image of the subject, a transmitting unit (16, 16a) that is configured to transmit the image captured by the imaging unit (11A, 11B) to an outside, and a magnetic field response unit; a magnetic field generation unit that is configured to generate a magnetic field for the magnetic field response unit to magnetically guide the capsule medical device; a receiving unit that is configured to receive the in-vivo image of the subject transmitted by the capsule medical device; a display unit (5, 42) that is configured to display the in-vivo image of the subject received by the receiving unit; an operation input unit that is configured to input operation information for magnetically guiding the capsule medical device; a control unit (45, 46) that is configured to control the magnetic field generation unit to guide the capsule medical device in accordance with the operation information input by the operation input unit; characterized in that the operation input unit is further configured to input selection information for selecting one combination from among combinations that combine at least two of a liquid surface area (Sws), a submerged area (Swb), and a liquid bottom area (Suw) as guidance areas into which the capsule medical device is guided, wherein at the liquid surface area (Sws), the capsule medical device is positioned near the surface (Ws) of the liquid including a case where the capsule medical device is in contact with an upper surface of a body cavity wall surface of the subject, at the submerged area (Swb), the capsule medical device is floating in the liquid, and at the liquid bottom area (Suw), the capsule medical device is in contact with a lower surface of the body cavity wall surface of the subject, and the control unit (45, 46) is further configured to switch the magnetic field to be generated by the magnetic field generation unit in accordance with the guidance areas selected by the operation input unit. a capsule medical device configured to be introduced into a body cavity of a subject and to float in a liquid introduced into the body cavity, the capsule medical device including an imaging unit (11A, 11B) that is configured to capture an in-vivo image of the subject, a transmitting unit (16, 16a) that is configured to transmit the image captured by the imaging unit (11A, 11B) to an outside, and a magnetic field response unit; a magnetic field generation unit that is configured to generate a magnetic field for the magnetic field response unit to magnetically guide the capsule medical device; a receiving unit that is configured to receive the in-vivo image of the subject transmitted by the capsule medical device; a display unit (5, 42) that is configured to display the in-vivo image of the subject received by the receiving unit; an operation input unit that is configured to input operation information for magnetically guiding the capsule medical device; a control unit (45, 46) that is configured to control the magnetic field generation unit to guide the capsule medical device in accordance with the operation information input by the operation input unit;