A total of 150 female Swiss mice were used to study the ability of water soluble propolis derivatives (WSPD) of Egyptian propolis to inhibit the proliferation and growth of Ehrlich ascites carcinoma (EAC) cells in mice. The mice were divided equally into three groups: the first was kept as a negative control group, the second received an intraperitoneal injection of 2.5 × 10(6) EAC and was kept as a positive control group and the third an intraperitoneal injection of 2.5 × 10(6) EAC and treated with propolis (50 mg/kg body weight) administered by gastric intubations 2 h prior to the intraperitoneal injection of EAC. The propolis was administered daily for 11 successive days. An examination of EAC cells revealed a reduction in the volume, total cell count, viable percentage and increase in the percentage of dead cells in the treated group with an increasing mean survival time (MST), increasing life span (ILS) percentage and treated vs positive control (T/C) percentage. Immunological studies revealed a significant increase in the lymphocyte transformation rate (LTR), phagocytic activity and killing power in the group treated with propolis. A haematological study of the parameters revealed leucocytosis in cancer-bearing mice and propolis-treated groups with granulocytosis and monocytosis. The erythrogram revealed a significant reduction in red blood cell (RBC) count in group 2. The result showed that the implantation of EAC in Swiss mice without treatment resulted in a significant decrease in total protein and albumin levels without a change in globulin level and a significant increase in creatinine level, while the third group that received propolis showed an improvement in these biochemical parameters compared to the normal control group.