Abstract: Male mice weighing 18～22 g were used. The aqueous extract of Angelica sinensis was prepared and sodium ferulate synthesized in our Institue.The clearance function of mononuclear phagocyte system was determined by Gongo red clearance test. The plasma Congo red concentration was decreased after an intravenous injection of Angelica sinensis at a dose of 16 g/kg. A similar effect was observed after intravenous administration of sodium ferulate at dosages of 100～200 mg/kg.The phagocytosis of the peritoneal macrophage in mice was estimated by adding cock red blood cell suspension to the macrophages. The phagocytosis percentage and phagocytosis index were increased when sodium ferulate was given either subcutaneously (0.2 g/kg/day) or orally (0.3 g/kg/day) for 4 days. Angelica sinensis (20g/kg sc)manifested a similar effect.The above results indicate that the phagocytosis function in mice was potentiated by treatment with Angelica sinensis and its constituent, ferulic acid.