Abstract: The control effects of the predators on the population of the brown planthopper,Nilaparvata bugens was studied in the light of rotation composite design of regression and the state-space method in this paper.The main predators in paddy field in Hailing Island in Guangdong province as the object population for constructing the equation of populations control index(IPC).It was emphasized that the state-space metod and IPC could be used to study the integrative control effcts of the predators on pest insects.