Heat storage material composition and use thereof

One or more embodiments of the present invention provide (i) a novel heat storage material composition, (ii) a heat storage material containing the heat storage material composition, and (iii) a transport container including the heat storage material. A heat storage material composition in accordance with one or more embodiments of the present invention may contain sodium sulfate 10-hydrate, sodium bromide, and sodium chloride, and have a melting point and a solidifying point within a range of 0° C. to 10° C.