Agrobacterium rhizogenes as a natural strain can be used to induce a variety of plants to produce hairy root.The research of hairy root tissues of many plants is able to produce secondary metabolites in a stable and efficient way,which is attracting more and more attentions.In this paper,we reviewed the characteristics,genetic mechanism and application of Agrobacterium rhizogenes and hairy roots.Meanwhile,we combined with our previous research to discuss the application prospects of hairy root in resource innovation and new drug sources development in M.cordata.