CCl(4) induces oxidative stress in various tissues by altering antioxidant enzymes defense system. In this study we investigated the chemical composition and protective role of Oxalis corniculata methanol extract (OCME) on CCl(4)-induced nephrotoxicity in rat. Presence of flavonoids, alkaloids, terpenoids, saponins, cardiac glycosides, phlobatannins and steroids was determined in OCME while tannins were absent. Total phenolic contents estimated were 7.76 ± 0.36 (mg gallic acid equivalents/g extract) while total flavonoid contents recorded were 6.92 ± 0.52 (mg rutin equivalents/g extract). Intraperitoneal injection of CCl(4) (1 ml/kg b.w., 20% in olive oil) once a day for seven days caused nephrotoxicity as evident by elevated levels of urinary specific gravity, RBCs, WBCs, creatinine, protein, urobilinogen and nitrite. Serum level of creatinine, urea, blood urea nitrogen were significantly increased while protein and creatinine clearance was decreased by CCl(4) treatment in kidney samples. Activity of antioxidant enzymes; catalase, peroxidase, superoxide dismutase, glutathione peroxidase, glutathione-S-transferase, glutathione reductase and glutathione concentration was decreased whereas lipid peroxidation and protein contents were increased along with histopathological injuries. Treatment with OCME caused significant recovery in changed parameters. It could be concluded that OCME has a protective role against CCl(4)-induced oxidative stress in rat, due to antioxidant effects of phenolics.