The increase in the incidence of hepatotoxicity resulting from exposure of individuals to toxic substances from the environment especially industrial hazards as well as toxicity from drug intake calls for search of more sources of hepatoprotective substances. African walnuts (Tetracarpidium conophorum) have been widely used not only as food but for various acclaimed medicinal purposes. The protective effects of Tetracarpidium conophorum seed oil against carbon tetrachloride (CCl4) - induced liver injury in wistar rats was evaluated. The oil was extracted with n-hexane from the walnut seed using Soxhlet apparatus. Forty eight male Wistar rats (100-120g) were used. These were divided into four groups of 12 rats each. Groups A and D were fed with normal rats’ feed and water while Groups B and C were fed with diet containing 10% extracted Tetracarpidium conophorum seed oil throughout the experiment. Group C and D received 200mg/kg CCl4 intraperitoneally once after 30 days of feeding. The administration of the African walnut oil attenuated the levels of serum aspartate aminotransferase, alanine aminotransferase, and liver lipid peroxidation in CCl4 – treated rats. Histopathological studies of the rats’ liver revealed that pretreatment of the animals with African walnut oil reduced the incidence of liver lesions induced by CCl4. African walnut oil also increased the antioxidant capacity of the rats by increasing reduced glutathione (GSH) content and decreased malondialdehyde (MDA) that was formed due to CCl4 administration in CCl4-treated rats. The results show that Tetracarpidium conophorum seed oil has hepatoprotective effect against CCl4 - induced liver toxicity.