The present invention provides a method of shortening pesticidal time of the baculovirus to pest, comprising: (1) preparing a pesticide composition (2) diluting the pesticide composition 100-3000 times and (3) spraying the diluted pesticide composition on third or older instars in fields wherein the pesticide composition comprises: (a) a ryanodine receptor insecticide or a diamides insecticide and (b) baculovirus, wherein the concentration of the ryanodine receptor insecticide or the diamides insecticide is 0.01-75% and the concentration of the nucleopolyhedrovirus is 107-1012 PIB/ml. The pesticide composition of the present invention can effectively reduce the lethal time to the pest compared to the baculovirus alone, and also can increase the control effect of the pest compared to the same concentration of the insecticide, when applied in field.
