Abstract:【Objective】To test the effect of Beauveria bassiana on SYSU-OfHe-C, a cell line from hemocytes of Ostrinia furnacalis. To provide a theory basis for application of B.bassiana in the prevention and treatment of O. furnacalis.【Method】MTT and CCK-8 were employed to test the virulence of B.bassiana on SYSU-OfHe-C. Optical microscope and scanning electron microscope were used to observe the growth of B.bassiana and its influence on the morphology of SYSU-OfHe-C cells. 【Result】The IC50 values of B.bassiana against SYSU-OfHe-C cells at 24 hours after treatment were recorded as 2.8×105 and 1.4×105 mL-1 respectively by MTT and CCK-8. Furthermore, under real-time monitoring with optical microscope, encapsulization and phagocytosis were not found and B.bassiana was highly competitive when the conidia of B. bassiana were inoculated in the culture of SYSU-OfHe-C cells at logarithmic stage reaching a final concentration of 3.5×104 mL-1 for B.bassiana. B.bassiana started to germinate at 10 hours after treatment, and meanwhile, SYSU-OfHe-C cells started to reduce in number and change in morphology. At 24 hours after treatment, B.bassiana grew the entire visual field. The nearly round SYSU-OfHe-C cells had elongated or turned into irregular shape. Aggregation, fragmentation, cavitation, protuberance and penetration of SYSU-OfHe-C cells caused by B.bassiana mycelia were observed.【Conclusion】B.bassiana can change cellular morphology of hemocytes of O. furnacalis, but cannot induce its immune responses.