The invention relates to a machine for sterilizing the topsoil of the ground, comprising the injection of superheated steam. The machine includes a water tank (5) and means for producing superheated steam and for conveying the latter to at least one supply nozzle (6). Said machine is characterized in that the means for producing superheated steam include: a spraying unit (8) that is in communication with the water tank and that includes a spraying chamber (9) in which a spraying device (10) is disposed in order to form an aerosol of fine water particles in said chamber； a unit (11) which can generate a conveying airflow that is moved through the spraying chamber (9) so as to drive the prepared aerosol out of said chamber； and a heating unit (12) which can raise the temperature of the aerosol such that the latter is converted into steam.
