Abstract: The effect of one entomopathogenic virus (PxGV) was studied on cabbage moth Plutella xylostella with hope to find management strategies of this insect, based on biological control. Bioassay showed that, this virus has high virulence and can be considered as the important agents on the control of this insect. The LC50 value of PxGV for second instar larvae of cabbage moth was calculated 448.58 g mm-2. The LT50 values for the same larvae with 749.89 and 1883.65 g mm-2 doses of PxGV were 6.04 and 6.85 days, respectively.