The alumina and alumina-coated rutile TiO2 samples were synthesized by the chemical liquid deposition method under various pH values and aging temperature. The prepared samples were characterized by Xray diffraction (XRD), Transmission electron microscopy (TEM), C-potential as well as X-ray photoelectron spectroscopy (XPS). The relationship between pH values, the dispersion stability, crystalline types and microstructure of alumina-coated rutile TiO2 samples were studied. It is indicated that the coating film exhibited amorphous hydrous alumina (at pH 3-7), boehmite (at pH 7-9) and bayerite (pH > 11), respectively. And the higher aging temperature was in favor of the elevation of boehmite content of coating film. As the boehmite content increased, the dispersion stability was gradually enhanced and the prepared sample exhibited optimum dispersion stability at pH 9 and aging temperature 200 degrees C, respectively. The increase of steric hindrance and electrostatic repulsion led to the promotion of dispersion stability via coating hydrous alumina film on the surface of rutile TiO2. The detection of Al-O and the significantly enhancement of Al-O Ti intensity confirmed that the film coating process should be main attributed to both chemical bonding and physical adsorption. (C) 2017 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.