Abstract: A device for regeneration and sterilization of earth, in particular compost earth, sand, especially playground sand or the like with steam in which a screw conveyor is located in an elongated treatment chamber for continuously moving the material to be treated in the treatment chamber from a feed side to a delivery side of the treatment chamber while mixing it. Further, at least one steam device is provided to introduce steam under pressure into treatment chamber by steam feed orifices along the lengthwise dimension of treatment chamber. Steam feed orifices can be provided in the wall of the treatment chamber. Alternatively or additionally, steam feed orifices can be provided in hollow shaft of the screw conveyor. To make it possible to continuously and automatically feed material into the treatment chamber a filling funnel is provided and steam feed orifices are arranged at a distance from the feed opening of the treatment chamber.