Abstract: The combinations of Hyphantria cunea NPV (HcNPV) and three different fluorescent brighteners BA,VBL, CBS-X were added to the artificial diet and the influence of synergists in concentration 25 ℃ and 14L /10D( h). The results showed that the fluorescent brightenersBA and VBL had higher insecticidal activity, CBS-X had notsignificant synergistic effect.