A respiratory mask system is provided, in which while wearing a respiratory mask system, force generated by movement of a users head and the like to induce laterally slipping a mask cushion may be reduced or absorbed. The respiratory mask system is provided with a mask cushion covering a nose, a nose and a mouth, or a full face. A first frame is connected with the mask cushion to supply respiratory gas under positive pressure. A second frame is connected with a headgear strap, in which the mask cushion is placed on a face side of the first frame and the first frame is placed on a face side of the second frame. The first frame is connected slidably with the second frame along a slide surface.
