A bending operation device includes a bending lever that is tiltably supported with an angle to a longitudinal direction of an operation section of an endoscope, a wire pulling member that includes a plurality of arm portions that are displaced according to tilting motion of the bending lever, a plurality of operation wires that are connected to the plurality of arm portions and that bend a bending portion provided in an insertion section of the endoscope according to displacement of the wire pulling member, and a plurality of pulleys that guide the plurality of operation wires to the plurality of arm portions, with the plurality of operation wires being substantially parallel to one another, when the bending lever is in a neutral position at which the bending portion is substantially straight.
