Beauveria bassiana is a potential biocontrol agent in sustainable pest management. But identification of native strain and its mass production is still a challenge. Moreover, information on compatibility status of B. bassiana with other commonly used insecticides and information on LC50 and LT50 values of this fungus are scanty. Therefore, an investigation was carried out to isolate new indigenous strain of B. bassiana in Sub Himalayan West Bengal, India. Further, its characterization and pathogenicity study were studied against Corcyra cephalonica under laboratory condition. Different media was evaluated for its growth. The morpho-molecular characterization revealed that the isolated fungus was a new indigenous strain, UBKV Bb1 of Beauveria bassiana (Balsam) Vuillemin. Rice grain was found to be the most suitable for sporulation (5.25 x 108 CFU/gm) as compared to other substrates viz., sorghum, maize, wheat, FYM and vermicompost. In the pathogenicity study, UBKV Bb1 strain resulted the highest pooled mortality of Corcyra cephalonica larvae (30.727%) with lowest LC50 (0.64 x 106 spore/ml) and LT50 (7.65 days) values than other strains. Imidacloprid 17.8 SL was more compatible than other tested insecticides, with radial growth of 28.5 mm and inhibition of 19.42% at 7 days after inoculation. This is the first report that demonstrates the pathogenic effect of an entomopathogenic fungus against Corcyra cephalonica larva in the Sub-Himalayan region of West Bengal, India.