An endoscope 10 includes a bending portion 16 provided on a distal end side of an insertion portion 11, bending wires 21 and 22 fixed on a distal end side of the bending portion 16, wire insertion portions 23 and 44 into which the bending wires 21 and 22 are inserted in the bending portion 16, and a channel tube 18 inserted and disposed in the insertion portion 11 and including an axial-directional through-hole 18h into which a treatment instrument 60 is inserted. The bending portion 16 includes a bending portion set 20 including a first bending piece set 30 including a plurality of bending pieces 31 and 32 rotatably coupled with each other; a tubular bending tube 40 including a distal end portion rotatably coupled with a proximal end portion of the first bending piece set 30 and capable of bending through a plurality of arrayed slits 41 and 42; and a second bending piece set 50 including a plurality of bending pieces 52 and 53 rotatably coupled with a proximal end portion of the tubular bending tube 40.