An endoscopic system comprising: a wire (180, 180a, 180b, 382, 384) configured to be pulled and loosened; a bending section (140, 142, 144) which is configured to be bent by the wire being pulled or loosened; an angle pulley (210, 220) coupled to a rotatable manual knob or an electric operation mechanism, the angle pulley (210, 220) configured to pull and loosen the wire (180, 180a, 180b, 382, 384) by a rotational movement caused by a rotation of the knob or the electric operation mechanism, thereby operating a bending state of the bending section (140, 142, 144); a flexible elongated tubular section which is connected to a proximal end of the bending section (140, 142, 144), the wire being inserted in the tubular section; and a shape information acquiring unit (270, 350, 550, 650) which is configured to acquire shape information indicating a shape of the tubular section; an adjustment unit (230, 240, 238, 330) which is configured to adjust tensile force applied to the wire (180, 180a, 180b, 382, 384) by changing a length of a path of the wire (180, 180a, 180b, 382, 384); characterized by: a memory unit which is configured to pre-store correspondent information including a relationship between the shape information and an adjustment value indicative of increase/decrease in the tensile force due to the shape of the tubular section; and a control unit which is configured to obtain the adjustment value corresponding to the shape information acquired by the shape information acquiring unit (270, 350, 550, 650) based on the shape information acquired by the shape information acquiring unit (270, 350, 550, 650) with reference to the correspondent information stored in the memory unit, generate an adjustment signal configured to drive the adjustment unit (230, 240, 238, 330) based on the adjustment value to adjust the tensile force, and output the adjustment signal to the adjustment unit (230, 240, 238, 330). a wire (180, 180a, 180b, 382, 384) configured to be pulled and loosened; a bending section (140, 142, 144) which is configured to be bent by the wire being pulled or loosened; a bending section (140, 142, 144) which is configured to be bent by the wire being pulled or loosened; an angle pulley (210, 220) coupled to a rotatable manual knob or an electric operation mechanism, the angle pulley (210, 220) configured to pull and loosen the wire (180, 180a, 180b, 382, 384) by a rotational movement caused by a rotation of the knob or the electric operation mechanism, thereby operating a bending state of the bending section (140, 142, 144); a flexible elongated tubular section which is connected to a proximal end of the bending section (140, 142, 144), the wire being inserted in the tubular section; and a shape information acquiring unit (270, 350, 550, 650) which is configured to acquire shape information indicating a shape of the tubular section; an adjustment unit (230, 240, 238, 330) which is configured to adjust tensile force applied to the wire (180, 180a, 180b, 382, 384) by changing a length of a path of the wire (180, 180a, 180b, 382, 384); a memory unit which is configured to pre-store correspondent information including a relationship between the shape information and an adjustment value indicative of increase/decrease in the tensile force due to the shape of the tubular section; and a control unit which is configured to obtain the adjustment value corresponding to the shape information acquired by the shape information acquiring unit (270, 350, 550, 650) based on the shape information acquired by the shape information acquiring unit (270, 350, 550, 650) with reference to the correspondent information stored in the memory unit, generate an adjustment signal configured to drive the adjustment unit (230, 240, 238, 330) based on the adjustment value to adjust the tensile force, and output the adjustment signal to the adjustment unit (230, 240, 238, 330).