Smilax aristolochiaefolia (Liliaceae) has been used in Mexican traditional medicine for the treatment of tumors, leprosy, anemia and as a tonic for skin infections and anemia. Aplastic anemia (AA) was induced in CD1 mice 8-12 weeks old distributed 10 animals each in Groups VSC, AA, AASa and AAr. Groups AA, AASa and AAr received benzene (2 ml/kg diluted v/v with corn oil) subcutaneously every three days until 20 dosages had been administered. The vehicular solution control group (VSC) received corn oil and the HC group (healthy control) received saline solution. Two days after the last benzene inoculation, groups AA and HC were bled and sacrificed to count blood and bone marrow cells. Group AASa received an aqueous S. aristolochiaefolia (0.4 g/kg) solution orally on days 3, 5 and 7 after the last dosage of benzene, meanwhile group AAr received no treatment after induction of AA (self recovery). On day 9 these groups were bled and sacrificed to count blood and bone marrow cells. Mice with aplastic anemia treated with S. aristolochiaefolia extract, recovered normal platelet levels and nucleated bone marrow cells as compared with the control, but the counts of erythrocytes and leukocyte were lower than controls (p<0.005). The aqueous extract of S. aristolochiaefolia (zarzaparrilla) restores hematopoeisis in the bone marrow of mice with aplastic anemia.