The chloroform extract of Ailanthus altissima stem bark and the alcoholic extract of Ziziphus spina christi roots were tested for their antischistosomal and hepatoprotective effects. The effect of schistosomal infection and treatment with both extracts on the activities of aspartate and alanine aminotransferases, acid phosphatase, 5’nucleotidase, glucose-6-phosphatase, lactate dehydrogenase, alkaline phosphatase and succinate dehydrogenase were estimated as measures of hepatic metabolic function, on free radical production in the form of lipid peroxides and on the levels of certain antioxidants namely, catalase, glutathione, vitamins C and E. In addition, the efficiency of the tested extracts on reducing the worm burden and ova counts in the infected mice was evaluated. The obtained data revealed that infection with S.mansoni increased lipid peroxides and decreased all antioxidant levels. On the other hand, the activities of acid phosphatase and 5`nucleotidase were higher while those of glucose-6-phosphatase, lactate dehydrogenase, alkaline phosphatase and succinate dehydrogenase were lower with respect to control. However, treatment with both A.altissima and Z.spina christi ameliorated the disturbed lipid peroxides, antioxidants and enzymes’ levels to nearly the control values, the chloroform extract of A.altissima showing a more pronounced improving effect against liver damage caused by parasitic infection. This study confirms the recent approach of many researchers for the use of plants in the treatment of liver diseases as alternatives to the classical chemotherapeutic drugs which may provide a low incidence of side effects.