Moringa oliefera have had a long history of use in traditional medicine. This work seeks to examine the phytochemical composition of the leaf of Moringa oliefera and the effects of its ethanol leaf extract on biochemical parameters (urea, alanine aminotransferase, aspartate transferase, alkaline phosphate, total globulin, total cholesterol, sodium, potassium) in Wistar Albino rats administered different concentrations of the extract. The rats were assigned into five groups of six (6) rats each. Group Awere given 0.9% normal saline and they served as control. Group B, C, D and E were administered 100 mg/kg, 250 mg/kg, 500 mg/kg, and 1 g/kg of extract respectively for 28 days. The blood of the animals was taken for biochemical studies. Results of phytochemical screening reveal that the plant contains alkaloids, cardiac glycosides, phenols, tannins, carbohydrates, reducing sugar, flavonoids. Biochemical studies show a significant difference (p < 0.05) in the aspartate transferase (AST) between the control and treated groups. Significant difference (p<0.05) was also noticed for alanine aminotransferase in the group treated with 1000 mg/kg of extract. It can therefore be concluded that oral administration of ethanol leaf extract of Moringa oleifera may be safe for the animals at the administered doses, since no adverse effects were detected from biochemical evaluation. It is also hepatoprotective on the animals as it enhances the functions of the liver enzymes.