The results regarding taurine pretreatment on CCl4-induced hepatic injury are controversial. To assess the therapeutic efficacy of taurine on rat liver injury, hepatic malondialdehyde, glutathione, and hydroxyproline levels together with morphologic alterations in the liver following CCl4 administration were investigated. The rats were divided into three groups. Taurine-treated animals received 15 ml/kg/day of a 5% taurine solution by a gastric tube for 5 days before administering CCl4 (2 ml/kg, intraperitoneally, in a single dose). CCl4-treated rats received the same amount of saline solution. Control animals received no treatment. The increase of hepatic malondialdehyde formation in the CCl4-treated group was partially prevented by taurine pretreatment, but taurine had no significant effect on the glutathione and hydroxyproline content in the CCl4-treated rats. Taurine pretreatment induced a marked beneficial effect regarding the prevention of hepatocellular necrosis and atrophy as demonstrated morphologically. In conclusion, these results suggest that taurine pretreatment might not significantly change the biochemical parameters, but prevents the morphologic damage caused by CCl4 in the early stages.