Abstract：Toosendanin is a tetracyclic triterpenoid compound extracted from the bark and seeds of Chinese medicinal Melia azedarach. At present，the known anticancer mechanisms of toosendanin include inducing tumor cell apoptosis， blocking cell cycle， inhibiting tumor cell migration and invasion. Recent studies have shown that toosendanin can reverse the resistance of tumor cells to chemotherapy. Some studies have shown that toosendanin has a bidirectional regulatory effect on autophagy of tumor cells. In the early stages of tumors， toosendanin can induce autophagic death of tumor cells； in the late stage of tumors， tumor cells degrade intracellular substances that have lost their function through autophagy， providing energy for other tumor cells. Kadirachtin can act as an autophagy inhibitor to inhibit tumor cell autophagy，revealing that chemotherapy drugs combined with autophagy inhibitors can serve as a new anti-tumor strategy. By reviewing the different mechanisms，pathways，and molecular targets of the anti- tumor effect of toosendanin，as well as its role and mechanism in reversing drug resistance，Chinese medicinal is linked to modern research， and the recently discovered molecular mechanisms are highlighted，which helps to discover new targets and cancer treatment drugs.