This paper gives a critical review of toosendanin, including its source, isolation, physical and chemical properties,industrial production, toxicology to vertebrates and insects, with special emphasis on the potential of development as a novel class of botanical insecticides. As far as the authors are aware, the chinaberry tree Melia toosendan Sieb. et Zucc. is mainly found in China and toosendanin was first isolated in China .We are the first group working on toosendanin as an insecticide. The unique properties of the toxic principles of toosendanin as an antifeedant, systemic and stomach poison as well as insect growth regulators, local availability, safe to the environment and com, patibility with the agroecosystem emphasize its ample potential in insect pest management system.