The invention provides a soil sterilizer capable of easily adjusting spraying quantity of a pump. The soil sterilizer (1) is provided with a plurality of liquid medicine pumps (36.36) capable of adjusting the spraying quantity of the liquid medicine in the process of pneumatically conveying the liquid medicine for sterilization and a plurality of liquid medicine injection claws (53.53) with the top end inserted into a farm for injecting the liquid medicine pneumatically conveyed by the plurality of liquid medicine pumps (36.36)Wherein the liquid medicine pumps (36.36) are arranged ON the outer edge at left or right side and are arranged along the fore-and-aft direction.