Autophagy is an evolutionarily well conserved cellular catabolic process.Cellular proteins and organelles are engulfed to autophagosomes and eventually delivered to lysosomes for degradation. Autophagy is closely associated with a variety of human diseases especially cancer. At present, it has been widely accepted that autophagy is a "double-edged sword" in cancer: it blocks tumorigenesis at the early stage, while it facilitates tumor development at the promotion and progression stage. Moreover, autophagy can be induced by chemotherapy and radiotherapy, which is generally play a pro-survival function. Thus, autophagy is an important target for cancer therapy, and suppression of autophagy to enhance the efficacy of cancer therapeutic agents is a novel strategy in cancer therapy under active clinical trials.