PROBLEM TO BE SOLVED: To provide a sterilizer of sand having a simple structure, for sterilizing sand economically and effectively.SOLUTION: The constitution of a sterilizer of sand comprises: a cylindrical body including an input port into which a liquid bactericide is introduced, for inputting sand to the upper side of the lower end therethrough, and a discharge port for discharging therefrom treated sand to the lower side of the upper end, and installed obliquely on a sterilizing place an inner plate having a circular cross section, installed on the floor board side of the cylindrical body from the periphery of the input port to the periphery of the discharge port a screw conveyor arranged so as to have a clearance with the inner plate, and moved from the input port position to the discharge port, while mixing sand with the bactericide and a motor for rotating the screw conveyor wherein the bactericide is returned to the lower side of the lower end through the interval between the inner plate and the floor board of the cylindrical body and the clearance so as to be reused.
