Novel β-MoO 3 and WO 3 hollow nanospheres were synthesized using a soft template of polymeric micelle with core–shell–corona architecture. Poly(styrene-b-[3-(methacryloylamino)propyl] trimethylammonium chloride-b-ethylene oxide) micelles (PS-PMAPTAC-PEO) with cationic shell block effectively produce core/shell composite particles through electrostatic interaction with anionic precursors WO 4 2− and MoO 4 2− . Transmission electron microscope (TEM) images of β-MoO 3 and WO 3 have confirmed the hollow structure with average outer diameter of 42±2 and 46±2nm, respectively; the hollow cavity diameters were found to be 16 ±1nm and 14±1nm for β-MoO 3 and WO 3 , respectively. The combination of nitrogen adsorption/desorption analyses and TEM observation confirmed the presence of disordered mesopores in the shell domain of β-MoO 3 and WO 3 hollow particles.