A reposition device for femoral shaft fracture is characterized by comprising base fastening screws, a base, a motor A, a motor B, a motor C, an H-shaped frame, a right stand column, a left stand column, a right wheel disc, a left wheel disc, a base-carrying bearing, a reposition frame, a rear square pipe, a front square pipe, a rear horizontal-movement support, a front horizontal-movement support, a fixed clamping piece, a tightening screw, ropes, a vertical locking screw and a horizontal locking screw; the reposition device simulates an F-shaped repositor and can be used for reposition of the front position, the back position and lateral positions of a femoral shaft; the ropes are selected as the transmission part of the reposition device, and the transmission part is of a dual-rope structure. By means of the reposition device, femoral shaft fracture reposition can be met on the premise that X-ray imaging is not shielded, percutaneous fixation is achieved and secondary damage does not exist, and a preparation is made for subsequent intramedullary nail implantation; the invention further provides a reposition method of the reposition device, the method is easy to operate, and femoral shaft fracture reposition can be achieved.