Malignant tumor is one of the main causes of human death. Radiotherapy, chemotherapy, targeted therapy and immunotherapy are common options for clinical tumor treatment. Although chemotherapy plays an important role in controlling tumor growth, its drug resistance seriously affects the prognosis of tumor patients. Autophagy is a biological self-digestion process in which cells degrade their macromolecules and destroy organelles through lysosomes. It plays a role in maintaining cell stability and protecting cells. At the same time, a large amount of evidence has proved that autophagy is closely related to tumor development, metastasis, targeted therapy and drug resistance. This article mainly analyzed the relationship between autophagy and drug resistance, and discussed the related molecular mechanism of autophagy in tumor chemoresistance, so as to provide new ideas for the development of specific autophagy-targeted anti-tumor drugs.