Endosomes are vesicular or tubular organelles that play important roles in transports of receptors and receptor―bound ligands during receptor-mediated endocytosis. The mechanisms of endocytic transports from clathrin-coated pits to lysosomes have been studied by many investigators. However, few studies were reported about the interactions between endosomes and cytoskeletons. In this study, Fc-receptor-mediated endocytosis in macrophages are investigated by quick-freezing and deep-etching (QF-DE) method combined with gold-labeled immune complex and “replica scraping method”.