Background: Reactivation of hepatitis B virus (HBV) is a fatal complication of chemotherapy. Occult HBV infection might be reactivated in patients undergoing chemotherapy or immunosuppression. However, the mechanism of HBV reactivation induced by chemotherapy or immunosuppression remains unclear. Material/Methods: HepG2.2.15 cells were treated with an autophagy inducer (rapamycin), an inhibitor (3-methyladenine, 3-MA), and dexamethasone. Autophagosomes were observed by a transmission electron microscope (TEM). LC3-I, LC3-II, and P62 were analyzed by western blot. HBV replicative intermediates were detected by southern blot. HBV DNA expression was quantitated with real-time polymerase chain reaction (PCR). The level of HBV surface antigen (HBsAg) in culture medium was examined by ELISA. Results: In this study, we find that dexamethasone stimulates HBV replication and protein expression by inducing au- tophagy in HepG2.2.15 cells. In contrast, autophagy inhibitor (3-MA) abrogates HBsAg secretion stimulated by dexamethasone. Conclusions: Our results suggest that dexamethasone stimulates HBV replication through autophagy. This might provide a novel insight into the mechanism of glucocorticoid-mediated HBV reactivation through autophagy, which might be a new therapeutic target.