An agricultural air injection apparatus comprising: a compressor for compressing air; an air tank which has a pressure gauge and a safety valve for presenting overpressure and stores compressed air of high pressure in a set pressure condition; a decompression valve for decompressing air pressure discharged from the air tank; a sprayer for spraying water in a particle state in order to make vapor contained in the supplied air; a distributor which uniformly distributes the decompressed air to a plurality of flow paths and has a control valve to open and close the flow paths; an air supply pipe which is buried in the soil where crops to be cultivated will be planted and has pores for supplying air passing through the distributor; and a controller which is connected to the compressor, the pressure gauge of the tank and the control valve of the distributor to control supply of the compressed air, characterised in that the air supply pipe comprises: a first temporary pipe and a second temporary pipe which are buried to a low depth in the soil and are branched at different depths to directly supply air to the roots of the crops; a drain pipe and a liquid fertilizer supply pipe which are respectively piped to the first temporary pipe and the second temporary pipe to supply water and liquid fertilizer if necessary; a fixed pipe which is fixed and mounted in the soil to be deeper than the temporary pipes; and a nonwoven fabric which surrounds the outer circumference of the fixed pipe and a wire mesh put on the outer surface of the nonwoven fabric in order to block inflow of foreign matters into the fixed pipe and prevent blocking of the pores. a compressor for compressing air; an air tank which has a pressure gauge and a safety valve for presenting overpressure and stores compressed air of high pressure in a set pressure condition; a decompression valve for decompressing air pressure discharged from the air tank; a sprayer for spraying water in a particle state in order to make vapor contained in the supplied air; a distributor which uniformly distributes the decompressed air to a plurality of flow paths and has a control valve to open and close the flow paths; an air supply pipe which is buried in the soil where crops to be cultivated will be planted and has pores for supplying air passing through the distributor; and a controller which is connected to the compressor, the pressure gauge of the tank and the control valve of the distributor to control supply of the compressed air, characterised in that the air supply pipe comprises: a first temporary pipe and a second temporary pipe which are buried to a low depth in the soil and are branched at different depths to directly supply air to the roots of the crops; a drain pipe and a liquid fertilizer supply pipe which are respectively piped to the first temporary pipe and the second temporary pipe to supply water and liquid fertilizer if necessary; a fixed pipe which is fixed and mounted in the soil to be deeper than the temporary pipes; and a nonwoven fabric which surrounds the outer circumference of the fixed pipe and a wire mesh put on the outer surface of the nonwoven fabric in order to block inflow of foreign matters into the fixed pipe and prevent blocking of the pores. a first temporary pipe and a second temporary pipe which are buried to a low depth in the soil and are branched at different depths to directly supply air to the roots of the crops; a drain pipe and a liquid fertilizer supply pipe which are respectively piped to the first temporary pipe and the second temporary pipe to supply water and liquid fertilizer if necessary; a fixed pipe which is fixed and mounted in the soil to be deeper than the temporary pipes; and a nonwoven fabric which surrounds the outer circumference of the fixed pipe and a wire mesh put on the outer surface of the nonwoven fabric in order to block inflow of foreign matters into the fixed pipe and prevent blocking of the pores.