The invention discloses a preparation method of a phase change heat storage material using inorganic glass as a heat storage medium, and belongs to the technical field of medium-and-high-temperature phase change heat storage materials. The method comprises the following steps: preparing the inorganic glass; grinding and drying the inorganic glass to prepare dried inorganic glass powder; and preparing the phase change heat storage material from the dried glass powder and a matrix material by a powder press-sintering or high-temperature infiltration process. The preparation method has the advantages of simplicity, low cost, and easiness in large-scale production, and is of great significance to high-temperature phase change heat storage materials.