An endoscope comprising: a bending tube including sequentially connected plural bending pieces constituting a bending section which is provided in a slim and elongated insertion portion and which is brought into a bending operation by remote control; a distal end section which is formed of a hard member is provided in the front end side of the bending tube and which constitutes the front end side of the insertion portion; a soft tube section which is provided in the base end side of the bending tube and which constitutes the rear end side of the insertion portion, the flexible tube section being connected to the base end side of the bending tube through a joint tube; a rubber covering member which is disposed to cover the bending tube and which has elasticity in order that both end portions (34, 35) of the covering member are fixed to the distal end section or the soft tube section by being fastened radially inward; and fixing means (32, 33) which comprise threads that respectively crush the both end portions (34, 35) of the covering member radially inward to fix the both end portions (34, 35) to the distal end section and the soft tube section; wherein the inner perimeter surface of the covering member is brought into intimate contact with the outer surfaces of the distal end section, the bending tube and the joint tube; characterized in that: the relationship represented by: 0.4 D < d < 0.95 D is established between a thickness d of the covering member fixed by fastening by the fixing means (32, 33) and the thickness D of the covering member before being fixed by fastening, the thickness D being within 0.2 mm and 0.8 mm. a bending tube including sequentially connected plural bending pieces constituting a bending section which is provided in a slim and elongated insertion portion and which is brought into a bending operation by remote control; a distal end section which is formed of a hard member is provided in the front end side of the bending tube and which constitutes the front end side of the insertion portion; a soft tube section which is provided in the base end side of the bending tube and which constitutes the rear end side of the insertion portion, the flexible tube section being connected to the base end side of the bending tube through a joint tube; a rubber covering member which is disposed to cover the bending tube and which has elasticity in order that both end portions (34, 35) of the covering member are fixed to the distal end section or the soft tube section by being fastened radially inward; and fixing means (32, 33) which comprise threads that respectively crush the both end portions (34, 35) of the covering member radially inward to fix the both end portions (34, 35) to the distal end section and the soft tube section; wherein the inner perimeter surface of the covering member is brought into intimate contact with the outer surfaces of the distal end section, the bending tube and the joint tube; the relationship represented by: 0.4 D < d < 0.95 D is established between a thickness d of the covering member fixed by fastening by the fixing means (32, 33) and the thickness D of the covering member before being fixed by fastening, the thickness D being within 0.2 mm and 0.8 mm.