A capsule endoscope (2) includes contact sensors (30b, 30c) that detects contact with an inner wall (14a) of a large intestine (14)； a magnet (27)； at least one imaging unit that captures the inside of the large intestine (14), and floats in liquid (15) when a specific gravity value of the capsule endoscope is around a value less than a specific gravity value of the liquid (15). An external magnetic field generating controller controls a magnetic field generator (5) for generating a guidance magnetic field to the magnet (27) from outside, performs a guidance control of the capsule endoscope (2) in the moving direction which is a lumen axis direction (C1). The magnetic field generating controller also performs a guidance control of the capsule endoscope (2) so that the capsule endoscope (2) is separated from the inner wall (14a) by guiding the capsule endoscope (2) in the upward direction (G) relative to the gravitational force and stopping the guidance alternately when the contact sensors (30b, 30c) detects contact with the inner wall (14a).
