Abstract: Bt (Bacillus thuringiensis) toxin has excellent insect-resistant property and environmental friendliness, which makes Bt toxin a substitution for most chemical pesticides and is widely used worldwide. As a consequence, overusing of Bt toxin has caused pest generating resistant to Bt toxin, and it seriously threatens the long-term effective of Bt crops and Bt insecticides. Although, joint using of various Bt toxins may produce synergistic effect or antagonistic effect, which leads to uncertainty and lower stability. As a result, it can’t be applied widely. RNAi(RNA interference) technology could silence specific gene expression. This technology has strong specificity and it doesn’t cause environmental pollution, which has great potential in pest control. The combined application of Bt toxins and RNAi technology is expected to open a new approach in pest control. In order to study the superiority of joint using of Bt toxin and RNAi technology, this paper reviews the application of Bt toxins and RNAi technology in respective fields, and the latest research of RNAi + Bt application. The states of RNAi + Bt application in controlling target pests is summarized in this paper, and it prospects the future implication of RNAi - Bt technology.