Provided is a wire stretcher, which is an apparatus which compresses the portion of the k-wire getting out behind the squeezing apparatus, the k-wire being passed through the wire retainer fitted on the bone surface, by rotating the holding part subsequent to being passed through the wire stretcher, thanks to the k-wire channel therein, and which enables, by rotating the outer body, the inner body with which the compressed k-wire is connected and the mid body to advance together in direction X, thereby stretching the k-wire.