A distal end bending piece 31 subjected to fastening processing for fastening a nail-plate portion 33 so as to allow seesaw movements is assembled on a proximal end side of a distal end rigid portion 14, a sleeve 44 is inserted from a rear side, and the sleeve 44 is fitted and fixed to the distal end rigid portion 14 in a state where a distal end bending piece 31 is housed in the sleeve 44, thereby allowing a first nail-plate portion 33a to elastically press an inner circumferential surface of the sleeve 44 and allowing a second nail-plate portion 33b to elastically press a bottom surface of a recessed portion 14b of the distal end rigid portion 14 at a predetermined contact pressure. Such a configuration enables a secure and stable electrical conduction between the distal end rigid portion 14 and the distal end bending piece 31, to allow the insertion portion 6 to be connected to a GND of a patient circuit without interfering with a reduction in a diameter of the insertion portion, thereby capable of ensuring electrical safety of an endoscope 2.
