The invention discloses a method for producing casein through dry sterilization. The method comprises the following steps: putting Qula into a dissolving vat, adding an auxiliary material, dissolving while the pH value is kept to be 9.5-10.0, filtering, performing centrifugal degreasing, regulating the feed liquid temperature to be 40 DEG C after degreasing, adding sodium hydrosulfite, sodium sulfite and sodium pyrosulfite, performing precipitation on casein through the diluted hydrochloric acid with the Baume density of 4.5, regulating the feed liquid pH to be 4.4-4.6 to enable the casein to be fully precipitated, and removing milk serum to obtain a precipitate; washing the precipitate with lukewarm water, dehydrating through plate frame pressure filtration and extrusion, performing material pelletization through a screen mesh, drying, pulverizing the pelletized and dried material, conveying the pulverized material to a material mixing bin, and fully sterilizing the material in the material mixing bin through ozone. According to the method, sterilization is realized by introducing ozone during the packaging link of casein production, so that microbes can be effectively killed; the operation is run in a dry environment and equipment is simple, so that equipment investment can be reduced, the product quality is stabilized, the automatic control level is improved, water and electricity consumption is reduced, and human resources are saved.