Barium titanate (BT) particles were coated with silica to improve their stability in water. The BT particles were prepared using a sol-gel method in a mixed solvent of ethanol and acetonitrile (weight ratio = 25/75) with additives of methylamine (MA) and acetylacetone. The silica coating was produced with the hydrolysis of tetraethylorthosilicate (TEOS) in the mixed solvent using a MA catalyst in the presence of the BT particles. TEM observation showed that the BT particles are spherical and have silica shells. The Zeta-potential measured for the coated BT particles with thick silica shells revealed that isoelectric point of the coated particles was almost consistent with that of silica particles. The size distribution of the coated particles was measured with dynamic light scattering (DLS) to examine the colloidal stability of the coated particles in water. The high stability of the coated particles was confirmed in the DLS measurement, and the averaged diameter of the coated particles obtained in this measurement was close to that obtained by TEM. Annealing of the coated particles produced fresnoite (Ba2TiSi2Og) crystallite particles.