An object of the present invention is to provide a bending angle adjusting mechanism for an endoscope which realizes simplification of adjustment work and simplification of manufacture by simplifying the structure and contributing to cost reduction, and an endoscope 1, a rod member 54 provided so as to extend in the longitudinal direction of the insertion portion 2 and having a threaded portion formed on the longitudinal direction surface thereof, a rod member 54 provided parallel to the longitudinal direction of the rod member A plate member 52 for inserting the rod member at both ends bent in a substantially right angle direction, an adjusting piece 55 screwed to the threaded portion of the rod member and positioned in the threaded portion, A guide member 53 having a portion sandwiched between the rod member and the plate member and disposed parallel to the rod member and the plate member and provided with guide passages 53 xa, 53 xb for guiding the position of the adjustment piece in the longitudinal direction of the insertion portion, And a rotation stopper member 51 for suppressing rotation about the member with respect to the longitudinal direction as an axis.本発明は、構造の簡素化により調整作業の平易化と製造の簡素化を実現しコスト低減化に寄与し得る内視鏡の湾曲角度調整機構を提供することを目的とし、そのための内視鏡1の湾曲角度調整機構50であって、挿入部2の長手方向に延出するように設けられ長手方向表面にねじ部が形成される棒部材54と、棒部材の長手方向に平行して設けられ略直角方向に曲げられた両端において棒部材を挿通させる板部材52と、棒部材のねじ部に螺合してねじ部の中で位置決めされる調整片55と、棒部材と板部材とに挟まれて固定される部分を有し棒部材及び板部材と平行に配置され調整片の位置を誘導する誘導路53xa,53xbを挿入部の長手方向に設けたガイド部材53と、棒部材がガイド部材に対して長手方向を軸として回転することを抑える回転止め部材51とを備える。