An endoscope comprising: an elongate insertion section in which an angle wire is inserted and that includes a bending section which is configured to be bent by applying a traction force to the angle wire; a bending operation section configured to operate a bending of the bending section; a shift mechanism configured to shift a bend radius of the bending section depending on the bending operation section; and a shift operation section configured to operate the shift mechanism, wherein: the bending section comprises an active bending section which is disposed at a distal end side of the bending section and which is configured to bend and a passive bending section which is disposed proximally from the active bending section and which is configured to be passively bent with an external force, the shift mechanism is provided in the passive bending section and comprises: front and rear side coils (23, 24), front side coil being axially separated from the rear side coil, and the angle wire being inserted and guided through the front and rear side coils (23, 24); and an actuation pipe interposed between the angle wire extending in the passive bending section and the rear side coil, the actuation pipe being supported to be moved in the extending direction of the front and rear side coils (23, 24), and being configured to adjust a gap between a proximal end of the front side coil and a distal end of the rear side coil, and a rigidity of the passive bending section is configured to be shifted while the actuation pipe is moved in the extending direction of the front and rear side coils (23, 24). an elongate insertion section in which an angle wire is inserted and that includes a bending section which is configured to be bent by applying a traction force to the angle wire; a bending operation section configured to operate a bending of the bending section; a shift mechanism configured to shift a bend radius of the bending section depending on the bending operation section; and a shift operation section configured to operate the shift mechanism, wherein: the bending section comprises an active bending section which is disposed at a distal end side of the bending section and which is configured to bend and a passive bending section which is disposed proximally from the active bending section and which is configured to be passively bent with an external force, the shift mechanism is provided in the passive bending section and comprises: front and rear side coils (23, 24), front side coil being axially separated from the rear side coil, and the angle wire being inserted and guided through the front and rear side coils (23, 24); and an actuation pipe interposed between the angle wire extending in the passive bending section and the rear side coil, the actuation pipe being supported to be moved in the extending direction of the front and rear side coils (23, 24), and being configured to adjust a gap between a proximal end of the front side coil and a distal end of the rear side coil, and a rigidity of the passive bending section is configured to be shifted while the actuation pipe is moved in the extending direction of the front and rear side coils (23, 24). the bending section comprises an active bending section which is disposed at a distal end side of the bending section and which is configured to bend and a passive bending section which is disposed proximally from the active bending section and which is configured to be passively bent with an external force, the shift mechanism is provided in the passive bending section and comprises: front and rear side coils (23, 24), front side coil being axially separated from the rear side coil, and the angle wire being inserted and guided through the front and rear side coils (23, 24); and an actuation pipe interposed between the angle wire extending in the passive bending section and the rear side coil, the actuation pipe being supported to be moved in the extending direction of the front and rear side coils (23, 24), and being configured to adjust a gap between a proximal end of the front side coil and a distal end of the rear side coil, and front and rear side coils (23, 24), front side coil being axially separated from the rear side coil, and the angle wire being inserted and guided through the front and rear side coils (23, 24); and an actuation pipe interposed between the angle wire extending in the passive bending section and the rear side coil, the actuation pipe being supported to be moved in the extending direction of the front and rear side coils (23, 24), and being configured to adjust a gap between a proximal end of the front side coil and a distal end of the rear side coil, and a rigidity of the passive bending section is configured to be shifted while the actuation pipe is moved in the extending direction of the front and rear side coils (23, 24).