Phagocytic capacities of both dendritic cells (DC) and macrophages(M?) in the DC-enriched fractions isolated from rat spleen were comparatively observed under electron microscope. Experiments were divided into two groups: in vitro and in vivo. In group 1, candida albicans(CA), cock red blood cells (CRBC) and CRBC opsonized with rat antiserum against CRBC (OCRBC) used as phagocytic markers were incubated with the DC-enriched fractions for 1h at 37℃ separately in vitro. In group 2, colloidal carbon (CC) (india ink) and heat killed Candida albicans (HKCA) were injected in vivo. The animals were sacrificed 18h later and DC-enriched fractions were isolated from the spleens. The results are as follow: generally, in the cytoplasm of DC, no phagocytic markers were identified except a few of DC ingested a small amount of CC in vivo and few CA occationally in vitro, while M? under the same conditions, ingested a lot of the substances mentioned above. It indicates that spleen M? phagocytose actively either to immunogenic or non-immunogenic, opsonized or non-opsonized particles (especially to opsonized particles), while DC in the same preparations are not.