Lead is a common environmental pollutant capable of causing acute and chronic illness (Vaziri, 2008). Generation of reactive oxygen species (ROS) has been postulated to be one of the possible mechanisms by which lead induces various toxic effects (Pande et al., 2001). It has been reported that lead increased the level of lipid peroxides and alter the antioxidant defense system in the hepatic tissues (Sandhir and Gill, 1995). Moringa oleifera leaves are rich in Vitamin A, B, C, α- tocopherols, flavonoids and carotenoids (Makkar and Becker, 1996). These vitamins and compounds act as antioxidants and help to stop lipid peroxidation chain reactions generated by free radicals from cell membranes (Nordberg and Arnér, 2001). Based on the observation that free radicals were generated during the pathogenesis processes induced by lead exposure, it has been presumed that supplementation of antioxidants could be an alternative method for chelation therapy (Flora et al., 2003). Therefore, the aim of this study was to investigate the hepatoprotective effect of aqueous leaf extract of Moringa oleifera following lead acetate administration to wistar rats. Twenty five adult male wistar rats were assigned into five equal groups (n=5). Group A served as control; group B animals were administered with 500ppm of lead acetate orally via drinking water daily; group C animals were administered 50mg/kg body weight of Silymarin (a known hepatoprotective drug) orally via drinking water prior to the administration of 500ppm of lead acetate; group D and E animals were administered orally with 400mg/kg (low dose) and 800mg/kg body weight (high dose) of aqueous leaf extract of Moringa oleifera respectively prior to the administration of 500ppm of lead acetate. The experimental period lasted for 28 days and all animals were cared for according to the guidelines of the National Institute of Health, (NIH, USA). The results revealed a significant elevation (P<0.05) of malondialdehyde (MDA) and significant reduction (P<0.05) in superoxide dismutase (SOD),catalase (CAT) and Glutathione (GSH) activity in group B (lead treated group only) compared to group A (control) and significant improvement (P<0.05) in SOD, CAT and GSH activity in groups D and E (treated with low and high doses of Moringa oleifera and lead respectively) when compared to group B but no difference (P>0.05) when compared to group A (control). Histopathologic studies of sections of the liver showed congestion of the central vein, enlargement of sinusoids°eneration of the hepatic plates in group B while group D & group E appeared normal when compared to the control. These observed changes in liver antioxidants activity and histology suggest that Moringa oleifera has hepatoprotective properties at low&high doses.