In an endoscope, a bend section (10) is disposed on a distal end side of an insertion section (7). A rotary body (35, 36), on which a proximal end portion of a wire (14) for a bend operation, which has a distal end portion connected to the bend section (10), is wound and held, is rotatably supported in a large-diameter section (15) on a proximal end side of the insertion section (7). Driving force transmission means (34), which converts linear movement of a working shaft (37-40) that is operable in a linear direction to rotational movement of the rotary body (35, 36), is provided in the large-diameter section (15). A driving source unit (8B) is detachably coupled to the large-diameter section (15) on the proximal end side of the insertion section (7). The driving source unit (8B) is provided with operation means which linearly moves the working shaft (37-40), when the driving source unit (8B) and the large-diameter section (15) on the proximal end side of the insertion section (7) are coupled, in accordance with an operation of a driving shaft (60, 61) that operates in a linear direction by a driving force from driving force generating means (19).