Fifty percent ethanol extract of Lythrum salicaria Linne root (LSR) was tested in vitro on antioxidant activity, and furthermore was investigated on antioxidative and fibrosis protecting activities in $CCL_4$-induced liver fibrosis rat model. Ratio of hepatic GSH/GSSG (reduced glutathione/oxidized glutathione) as bio-parameter of antioxidant level in $CCL_4$ plus LSR-treated rats for 6 weeks significantly increased from 2.8- to 5.7-fold than that of $CCL_4$-treated rats at p < 0.05. Thiobarbituric acid reactive substances (TBARS) contents in $CCL_4$ plus LSR-treated rats ranged from 1.57- to 2.19-fold of normal rats and were lower than those in $CCL_4$ plus silymarin-treated rats ($1.78{sim}2.46$-fold of normal rats) (p < 0.05). Amounts of hydroxyproline of liver tissue showing the content of total collagen, a parameter of fibrosis, in $CCL_4$ plus LSR-administrated rat livers were $4.9{sim}8.8{mu}g$/mg ($-47{sim}-71%$, compared with that in $CCL_4$-treated rat livers ($16.6{mu}g$/mg tissue), which were significantly lower than those in $CCL_4$ plus silymarin-administrated rats being $8.4{sim}11.7{mu}g$/mg ($-30{sim}-50%$). This collagen reducing effect of liver tissue in $CCL_4$ plus LSR-treated rats was supported by histological observation using microscopy assay. From the results, we conclude that the root of L. salicaria have efficient antioxidant potential and effective antifibrotic activities.