Provided is a capsule endoscope including a capsule body, a fin portion, and a sack portion, the capsule endoscope being capable of moving easily even in a situation where the movement thereof is likely to be obstructed. This capsule endoscope 1 includes: a capsule body 3 including a forward imaging element that images a forward side and a backward imaging element that images a backward side a fin portion 4 in which a magnet that is displaced in response to an alternating magnetic field is mounted and which vibrates by being elastically deformed by the displacement of the magnet and a sack portion 5 to which a front end 4b of the fin portion 4 is bonded at a position shifted downward from an axial line of the capsule body 3, and which is attached to the capsule body 3 in such a way that a rear end side of the capsule body 3 is inserted into the sack portion 5 and the sack portion 5 is elastically deformed to make close contact with the periphery of the rear end side, the sack portion 5 being provided with an opening of a hollow portion near the front end of the fin portion 4. The fin portion 4 moves by vibrating in an up-down direction in a liquid medium.