Abstract: Third instars larvae of cotton bollworm,Helicoverpa armigera,were infected with different concentrations of Helicoverpa armigera nucleopolyhedrovirus(HaNPV).Survivors were collected respectively and reared in laboratory room.Mortality rate of the larvae,average weight of the single pupa and pupation rate were observed in parental generation and successive filial generations.The results showed that the virus not only led to death of larvae in parental and folial generation,but also impacted the average weight of the single pupa and pupation rate,especially to the parental and the first folial generation.The experimental data indicated that the virus could weaken the host in folial generations,which could control populations of the host for a long time.Meanwhile,polymerase chain reaction(PCR) amplification of polyhedrin gene sequences demonstrated that the virus was present in eggs and pupae whose parents were infected.This method might provide a better understanding of nucleopolyhedrovirus which could transmit from parental generation to folial generation. The research would play an important role in utilizing the virus effectively to control the pest persistently.