An endoscope has a bendable portion configured to be operated to be bent within one plane which is parallel to an axial direction of an endoscope insertion part 13 on a distal end side of the endoscope insertion part 13. An outer peripheral surface of the bendable portion is covered with an elastic tube 31 having flexibility. A rigidity of the elastic tube 31 in directions L and R orthogonal to bending operation directions U and D is higher than that of the elastic tube in the bending operation directions U and D.