Objective To investigate the effects of mechanical damage on prostaglandin E2 (PGE ;) secretion in human skin keratinocytes, and explore its possible mechanism. Methods Human skin keratinocytes (HaCaT) cultured in vitro were divided into injury group, NADPH oxidase (NOX) inhibitor diphenyleneiodonium chloride (DPI) pretreatment group and antioxidant N-acetylcysteine (NAC) pretreatment group. Mechanical damage cell models were established by scratch method, and HaCaT cells without model establishment were served as control group. Cells and culture supernatant were collected from injury group, DPI pretreatment group and control group at different time points after model establishment, fluorescent probe and chemiluminescence method were employed to detect the intracellular reactive oxygen species (ROS) generation and NOX activity respectively, and the mass concentration of prostaglandin E2 (PGE ;) in culture supernatant in each group was determined by enzyme-linked immunosorbent assay. Results At each time point after model establishment, the intracellular ROS generation and NOX activity in injury group and DPI pretreatment group were significantly higher than those in control group (P < 0.05 or P < 0.01), and the intracellular ROS generation and NOX activity in DPI pretreatment group were significantly lower than those in injury group (P <0.05 or P <0.01). The mass concentrations of PGE ; in culture supernatant in injury group, DPI pretreatment group and NAC pretreatment group were significantly higher than that in control group (P < 0.01), while the mass concentrations of PGE2 in culture supernatant in DPI pretreatment group and NAC pretreatment group were significantly lower than that in injury group at each time point after model establishment (P < 0.01). Conclusion PGE secretion in human skin keratinocytes may increase after mechanical damage, which may be associated with oxidative stress mediated by increased intracellular ROS generation and NOX activity.