Molten salt method was applied to prepare LiCoO2 powder in this paper. The starting materials were calcinated at different temperatures from 550 to 800 degrees C in air and LiCoO2 samples with a series of sizes were obtained. The particle morphology, structural characteristic and particle size effect of LiCoO2 were investigated by scanning electron microscope (SEM), X-ray diffraction (XRD) and laser Raman spectroscopy. It shows that the LiCoO2 samples obtained are homogenous and the particle size can be easily controlled by preparation temperature. Two different phases can be found in the LiCoO2 samples prepared in this work. The shifting and broadening of Raman spectra were mainly attributed to the particle size effect of LiCoO2. (C) 2008 Published by Elsevier B.V.