A system for planning pedicle screw fixation includes: a C-arm configured to capture a spinal image of a patient; an insertion path provider configured to provide an entry point and an insertion endpoint of a pedicle screw on a C-arm image; a registrator configured to calculate spatial coordinates of the entry point and the insertion endpoint based on a reference coordinate system; a guider configured to determine an insertion position of the pedicle screw based on the spatial coordinates of the entry point and the insertion endpoint, and guide a probe to be inserted toward the entry point according to the insertion positions; and a screw determiner configured to determine a length condition of the pedicle screw by obtaining coordinates of a start point at which the probe is inserted and becomes in contact with a bone.