Some entomopathogenic fungi, such as Cordyceps militaris, Beauveria bassiana, Isaria fumosorosea, Metarhizium anisopliae, Isaria farinosa, and Beauveria brongniartii, have been reported to play an important role in termination of population outbreaks of forest defoliators in Japan. In this experiment, a culture-independent method using quantitative real-time Polymerase Chain Reaction (qPCR) was employed to develop specific detection and quantification of those six entomopathogenic fungi from soil and dead cocoon samples. Soil samples were collected from larch plantations (LP) and beech forest (BF). Dead larch sawfly cocoons were collected from the LP. Some specific primer pairs for each fungus were designed and tested for their specificity. A primer pair was successfully designed for C. militaris, B. bassiana, I. fumosorosea and M. anisopliae, but still unsuccessful for I. farinosa and B. brongniartii. Standard curves were obtained for both genomic and soil DNA for all the four fungus (R2>0.980). C. militaris was detected from soil samples in BF, but B. bassiana, I. fumosorosea and M. anisopliae were not from all soil samples. Detection from dead cocoon samples showed positive for B. bassiana and M. anisopliae. The qPCR method developed in this study seems effective, rapid, sensitive, and specific for studying these fungi.