Monodisperse, spherical alumina powders were prepared by the controlled hydrolysis of aluminum triethoxide in a solution consisting of various alcohol and acetonitrile. As H2O concentration increased, the particle size was decreased and size distribution was more sharp. Prepared particle's morphology was spherical when heptanol and decanol were used as solvent. Amorphous powders which were prepared crystallized to γ-alumina at 1000 ℃ and converted to α-alumina at 1150 ℃.