Hollow MCM-41 microspheres were obtained by removing the templates of poly (styrene-gamma-methacrylic propyltrimethoxysilane)/MCM-41 [P(St-MPS)/MCM-41] core/shell composite microspheres prepared using P(St-MPS) microspheres contained in soap-free emulsion and cetyltrimethylammonium bromide as cotemplates. XRD, TEM, and IR measurements show that the pore channels of MCM-41 shell were hexagonally ordered and that the diameter of the hollow microspheres and the thickness of the shells were about 260 and 30 nm, respectively.