Mesoporous silica materials with ordered hexagonal and parallel-arranged pore channel have been synthesized using cetyl trimethylammonium bromide as a template and Na2SO4 as counterions. Their ordered mesostructures were characterized by infrared spectroscopy, X-ray diffraction patterns, scanning electron microscopy, transmission electron microscopy, and nitrogen sorption analysis. The effects of Na2SO4 concentration on variations of morphology, specific surface area, and pore size were discussed; the results show that a high concentration of Na2SO4 induces the formation of crystal threads with a "tubules-within-tubule" structure, and also leads to mesoporous silica materials with spherical, fabaceous, sheet-like, or prismatic shapes. The results also show that a high concentration of Na2SO4 can make the pore size decrease, but cannot change pore wall thickness, demonstrating the stability of the hexagonal-shaped pores.