The invention provides a novel corner connector. Two ends of the corner connector are respectively and fixedly connected with rims of a window frame or a window sash, so that two adjacent right-anglededges in the window frame or the window sash can be more stable after being connected by the corner connector. The novel corner connector comprises a first corner connector and a second corner connector which penetrate in frame grooves of adjacent frames of a window corner in the window frame or window sash, wherein the front ends of the first corner connector and the second corner connector areattached to form a right angle and are fixed together by a bolt; the front end parts of the first corner connector and the second corner connector are respectively provided with a first upper base surface, and clamping hooks are fixedly arranged at the rear edge positions of the first upper base surfaces; the middle parts of the first corner connector and the second corner connector are respectively provided with a lower base surface, the rear parts of the first corner connector and the second corner connector are respectively provided with a second upper base surface, and a positioning hole is arranged in the second upper base surface; the first corner connector and the second corner connector are respectively provided with an inclined surface which extends from the rear end of the secondupper base surface to the rear end of the lower base surface. The novel corner connector provided by the invention has the advantages that the two ends of the novel corner connector are respectivelyand fixedly connected with the frame, and the connection strength of the corner connector and the frame is improved, so that the service life of the window frame or the window sash is longer.