An endoscope includes: an insertion portion in which a distal end portion and a bending portion that is bendable in a desired direction are arranged and an inclined face that is formed in the distal end portion, the inclined face being formed so as to inclinedly intersect with a distal end face of the distal end portion and also a side face adjoining the distal end face, a ridge line formed intersecting with the distal end face and a direction in which the bending portion bends being formed substantially orthogonal to each other, wherein, by contacting against an inner wall of a curved portion of a duct into which the insertion portion is inserted, the inclined face varies a posture thereof so that the insertion portion is rotated and a bending direction of the bending portion matches a curving direction of the curved portion.
