Background : A soil-borne pathogenic fungus, Ilyonectria radicicola (Cylindrocarpon destructans) species complex causing ginseng root rot is the major pathogen on ginseng. DNA extraction from soil is necessary to confirm the presence of ginseng root rot pathogen, I. radicicola. Methods and Results : In order to the increase the detection sensitivity of pathogens present in the soil, the existing soil DNA extraction method was modified to inctease the efficiency of the PCR reaction and to increase the amount of soil samples that can be analyed once by 500 times. For increase the DNA concentration, phenol : chloroform : isoamylalcohol (25 : 24 : 1) were used instead of chloroform : isoamylalcohol (24 : 1), and the sensitivity of PCR was increased by using purification kit. Conclusion : The modified DNA extraction method can detect ginseng root rot pathogen (I. radicicola) with DNA extraction and purification higher than the conventional method.