[Objectives]  A strain of entomogenous fungi was obtained from dead Holotrichia parallela Motschulsky larvae collected in the field, and its species and culture characteristics, as well as its virulence to four important agricultural pests, were measured and compared. [Methods]  Fungal growth media were purified and cultured, and fungal morphology identified under a microscope. The colony growth characteristics of the fungal strain was observed, and its growth rate, spore yield and germination rate determined. The pathogenicity of the strain to the four pest species was determined by bioassay. [Results]  The fungus was identified as Beauveria bassiana. Morphological differences in colony characteristics were apparent between fungal colonies cultured on PDA vs SDAY media. The growth rate on PDA was significantly higher than on SDAY, but the spore germination rate was significantly lower. The two media did not differ significantly in sporulation rate. The fungal strain was most pathogenic to Ostrinia furnacalis and Chilo suppressalis larvae, which were significantly more sucesptible to it than Agrotis segetum and Mythimna separata. The fungus was most virulent to 5th instar larvae of the same pest species than to 2nd instar larvae, and it was significantly more virulent to older instars of Agrotis segetum and Mythimna separata than to younger instars. [Conclusion]  B. bassiana is pathogenic to the larvae of important agricultural pests such as Chilo suppressalis, Ostrinia furnacalis, Agrotis segetum and Mythimna separata, but its pathogenicity varies between species and instars. Nonetheless, the maximum corrected mortality of Chilo suppressalis and Ostrinia furnacalis larvae after infection with this fungal strain was > 94%, which indicates that it has potential as a biological control for these pests.