1. A 3-dimensional tracking system, comprising: a photographing unit for photographing an object; a recognizing unit for recognizing a marker attached to the object by binarizing an image of the object photographed by the photographing unit; an extracting unit for extracting a 2-dimensional coordinate of the marker recognized by the recognizing unit; and a calculating unit for calculating a 3-dimensional coordinate from the 2-dimensional coordinate of the marker by using an intrinsic parameter of the photographing unit.