The invention discloses shoe mould casting gypsum powder. The gypsum powder is prepared from gypsum alpha, quartz, cristobalite, a Targon-GA1 retarder, ammonium chloride and a P803 powdery antifoaming agent serving as raw materials by the following steps of: preparing the gypsum alpha, the quartz and the cristobalite into fine powder with particle sizes of 12 to 15 mu m, 11 to 13 mu m and 9 to 11 mu m respectively; and adding the fine powder and the Targon-GA1 retarder, the ammonium chloride and the P803 powdery antifoaming agent in the components into a material mixer and uniformly mixing the materials to obtain the gypsum powder. The shoe mould gypsum powder prepared from the gypsum powder alpha, and other inorganic refractory materials and additives according to a specific proportion has the characteristics of high operation performance, adjustable setting time, high strength, high collapsibility, stable size and the like. The gypsum powder solves the technical problems of low production efficiency, poor operation performance, long setting time, low strength and easy deformation existing in the prior art.