Endoscope

An endoscope comprising:

• an insertion portion to be inserted in a lumen, the insertion portion including a distal end on an insertion direction side and a proximal end on an opposite side of the insertion direction;
• an objective optical system arranged at a distal end portion of the insertion portion and configured to obtain an image of a subject to be examined in the lumen;
• a treatment instrument raising base arranged on a more distal end side of the insertion portion than the objective optical system and configured to control an inclination angle of a treatment instrument inserted through the insertion portion toward the insertion direction;
• and
• a restricting portion configured to restrict an angle at which the treatment instrument directed by the treatment instrument raising base is protruded outside the insertion portion, the restricting portion being provided at the distal end portion of the insertion portion,
• wherein a straight line connecting the treatment instrument raising base and the objective optical system is substantially parallel to a longitudinal axis of the insertion portion,
• the restricting portion is provided so as to be located on a line segment connecting the treatment instrument raising base and the objective optical system when the objective optical system is viewed from right in front, and the restricting portion includes a restricting surface which contacts the treatment instrument, and
• when the treatment instrument raising base is maximally inclined, an angle of a central axis of the treatment instrument with respect to the longitudinal axis which is along the insertion direction of the insertion portion becomes equal to or smaller than an angle of the restricting surface with respect to the longitudinal axis.