Abstract: Autophagy is a dynamic process which subcellular membranes undergo morphological changes that lead to the degradation of cellular cytoplasmic organelles and macromolecules. It is regulated by the mammalian target of rapamycin (mTOR)dependent or independent signaling pathways. It has been demonstrated that autophagy is induced or inhibited in various tumor cells, and it is closely related with cell survival and drug resistance. Because of the complex relationships with cell death, the roles of autophagy in cancer development, treatment, and drugresistance are not the same, and thus controlling autophagy properly may become one of new means of cancer therapy.