Abstract: A surgical navigation system includes a surgical tool; an optical tracking system; and a calibrating device. The optical tracking system includes a light source, configured to emit infrared radiations; an optical tracker; a camera; and a data processor. The calibrating device is configured to calibrate the surgical tool tracked by the optical tracking system. The calibrating device includes a reflector; and a holder. The light source is arranged to irradiate a profile of the surgical tool held by the holder. The camera is arranged to detect the infrared radiations, which are reflected by the surgical tool and by the reflector so as to capture images of the profile of the surgical tool. The data processor is configured to compute the pose of the surgical tool from the captured images of both the optical tracker and the profile of the surgical tool.