Montmorillonite (Mt) is a clay mineral with expandable layer structure. Mesoporous pillared montmorillonite can be prepared by introducing gallery templates, such as simple metal cations, quaternary ammonium cations, long chain amines, and hydroxyed inorganic metal ions. In this paper, inorganic-organic pillared montmorillonite intercalated by aluminium and alkyl ammonium chloridize (HDTMA-Cl) was successfully prepared by ultrasonic treatment, and the physicochemical properties of the materials were systematically characterized by XRD, FT-IR, SEM and TEM techniques. The d(001) basal spacings and microstructures of Mt-Al-HDTMA were characterized by XRD. The function group, crystal surface morphology, structural and chemical analysis of Mt-Al-HDTMA were measured by FT-IR, SEM, TEM and EDX. The results indicated that ultrasonic method might accelerate the diffusion of the intercalating species, which enhanced the textural properties and the morphologies. The results also suggested that aluminium and HDTMA-Cl reagent entered the interlayer of Mt, and that the crystal structure of the final Mt was preserved.