Core shell microspheres with BEA and FAU zeolite structures (denoted as BEA FAU) were prepared through a two-step hydrothermal crystallization process in which a beta-zeolite was used as silicon source for the synthesis of Y zeolite as well as a template for the formation of hollow sphere. Scaning electron microscopy and intrusive mercury experiments displayed the as-synthesized sample had extra-large pores of 2- 3 mu m; a possible formation mechanism of BEA FAU hollow spheres was proposed and discussed.