Abstract: In a soil processing method of the present invention, a microwave radiator is made to move into soil, and microwaves are thereafter radiated from the microwave radiator to soil to be processed. As a method for making the microwave radiator move into soil, a method in which an underground mover incorporating the microwave radiator is made to move underground while making a cultivator move underground by means of a underground-moving claw mechanism similar to a chisel or subsoiler, a method in which the microwave radiator is vertically thrust into and drawn out from soil by a power arm, or a method in which the microwave radiator is vertically thrust into and drawn out from soil by using one of various vertical excavation devices may be used. According to the present invention, the influence of microwaves on soil in a deep region not easily influenced by microwave radiation to a farm surface can be effectively improved to ensure that various functions useful in agriculture, e.g.