A manipulator system including a manipulator that includes an insertion part having a main section and a bending section, a bending-section driving portion, and a linear member inserted through a sheath fixed to the main section at one end thereof, the linear member connecting the bending section and the bending-section driving portion through the main section and transmitting a driving force generated by the bending-section driving portion to the bending section; an operation input unit via which an operation instruction to the bending section is input; a sheath-tension detecting portion that detects the tension in the sheath; a compensation-value setting portion that sets a compensation value for a bending control signal on the basis of the tension in the sheath, and a control unit that generates the bending control signal and sends the bending control signal corrected with the compensation value to the bending-section driving portion.