An outdoor sleeping mat and a sleeping mat set includes a sleeping mat main body, a plurality of transverse supporting belts and a plurality of vertical supporting belts. The sleeping mat main body has a cavity, and the transverse supporting belts and the vertical supporting belts are disposed in the cavity and connected to the sleeping mat main body. The plurality of vertical supporting belts are distributed at two sides of the sleeping mat main body in a width direction, and the plurality of transverse supporting belts are arranged side by side in a length direction of the sleeping mat main body. The outdoor sleeping mat enhances the structural reliability of the sleeping mat main body through the plurality of transverse supporting belts and the plurality of vertical supporting belts, so that the whole outdoor sleeping mat has better supporting performance.