The leaves of Argemone mexicana L. (Papaveraceae) are used in traditional medicine in Burkina Faso to treat a variety of diseases. In the “Cascades” region, many people use the leaves of the plant for the treatment of liver ailment. An aqueous extract and a crude leaf powder suspension were tested for their antihepatotoxic action against CCl4-induced hepatitis in Wistar rats. The aqueous extract (250 mg/kg, p.o.) and the crude leaf powder suspension (250 mg/kg, p.o.), orally administered, significantly attenuated the elevation of serum enzymes (GOT, GPT, ALKP) and direct bilirubin (Dbil) induced by CCl4 intoxication in rats. These actions were comparable to that of silymarin used as reference substance. For the acute toxicity test any mortality was seen at doses up to 2500 mg/kg.KEYWORDS: Argemone mexicana, antihepatotoxic, hepatoprotective, aqueous extract.