The leaves of Moringa oleifera plant are documented as active pharmaceutically agent with high antioxidant activity. In this study the protective effect of ethanolic leaves extract (ELE) and aqueous leaves extract (AQLE) of Moringa oleifera and Silymarin (SIL) were investigated against cyclophosphamide (CYP) injury on liver of rats. Fifty males of albino rats were divided into five groups, as follows: 1) control group - received distilled water orally; the second group was CYP group which injected with cyclophosphamide at dose of 150 mg/kg through i.p. to rats twice; one dose on the15Th day and another on the 30Th day. Other 3 groups basically injected with CYP as a group 2 Moreover the 3rd group i.e.( ELE + CYP) group the rats were administered with ELE at dose 500 mg/kg/day orally through an intra-gastric tube for consecutive 14 days, before and after CYP injection. The 4Th i.e. (AQLE+CYP group) the rats were given AQLE at dose 500 mg/kg/day orally for consecutive 14 days, before and after CYP injection. 5) SIL+CYP group - Rats were administrated with SIL at dose of 100 mg/kg/day by gavage for consecutive 14 days, before and after CYP injection. One day after the last treatment, blood samples and livers werewc . collected for histopathological investigations and biochemical determinations .The level of lipid peroxidation, thiobarbituric acid-reactive substances (TBARS), serum albumin, total protein, alanine aminotransferase (ALT) and aspartate aminotransferase (AST), alkaline phosphatase (ALP) and lactate dehydrogenase (LDH) values were evaluated. TBARS, AST, ALT, ALP, and LDH in serum were elevated significantly increased (P < 0.05) in CYP group, compared to control group, while total protein and albumin were decreased compared to control group and other groups. Histopathologically, it was observed hepatocytes damage in CYP induced group compared with the control group and other groups. In conclusion, Moringa leaves extracts exhibited antioxidant activity by the presence of free radical quenching scavenger constituents which protect liver from cyclophosphamide injury.