OBJECTIVE : The purpose of this study was to investigate plumbagin (PL) on liver fibrosis in vitro and in vivo and to explore the underlying mechanisms. METHODS : Carbon tetrachloride (CCl4) was used to establish a rat liver fibrosis model, primary hepatic stellate cells (HSCs) were isolated from the rat liver, and fibrosis-related indicators were detected. RESULTS : The results revealed that PL significantly prevented CCl4-induced liver fibrosis, as evidenced by the attenuation of histopathological changes, the decrease of MDA and the increase of SOD and GSH-P X . In addition, PL downregulated the mRNA levels of NOX4 and procollagen I; the protein expression levels of NOX4 and p-IκB; and the transcriptional activity of NF-κB in liver fibrosis rats. Moreover, PL significantly decreased ROS expression, protein expression of α-SMA and collagen III, and activation of NF-κB and inhibited the nuclear translocation of NF-κB p65 in IL-1β-stimulated HSCs in vitro. CONCLUSIONS : The results of our study indicate that PL can mitigate liver fibrosis in vitro and in vivo, which may be related to the ROS-mediated NF-кB signaling pathway.