We report the synthesis and characterization of a novel mesoporous material with a face-centered cubic (fcc) symmetry and intrinsic bimodal pores. Moreover, an icosahedral (ICO) mesostructure with both meso- and macroscale 5-fold symmetry is observed. We propose a hard-sphere packing (HSP) mechanism for the formation of mesoporous materials by assuming preformed robust surfactant/silicate composite micelles being hard spheres. In comparison to the conventional liquid crystal templating (LCT) or cooperative self-assembly (CSA) mechanism, our contribution provides an important advancement of knowledge in the study of mesostructured materials.