Zeolite beta with SiO 2 /Al 2 O 3 ratios from 30 to 730 was synthesized by a steam-assisted crystallization method, and the crystallized products obtained within 24 h were characterized by means of chemical analyses, XRD, FE-SEM, 2 9 Si-MAS NMR, N 2 adsorption, and temperature-programmed decomposition of tetraethylammonium cation occluded in the micropores of zeolite beta. Based on these results, the crystallization mechanism is discussed herein. It was found that agglomerates of nano-particles were formed from a dry gel before the development of a periodical structure in a long-range order, which can be detected by XRD. After several hours of crystallization, morphological changes in nano-particle agglomerates proceeded to give highly crystalline zeolite beta.