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. A respiratory mask system, which is provided with a mask cushion covering a nose, a nose and a mouth or a full face, a first frame connected with the mask cushion enabling to supply respiratory gas under positive pressure from a means for supplying respiratory gas under positive pressure, and a second frame connected with a headgear strap, in which the mask cushion is placed on a face side of the first frame, the first frame is placed on a face side of the second frame, a slide surface is formed at least a side of the first frame facing the second frame or a side of the second frame facing the first frame and the first frame is connected slidably with the second frame along the slide surface.
