Using neutralized-hydrolysis and self-dissociate products of TiOSO4 as Ti sources respectively, the synthesis of ultra-fine barium titanate (BaTiO3) powders under wet chemical mixing-calcining process was studied. The structure of BaTiO3 powders were characterized by XRD, TG/DTG, ICP, Raman and SEM analysis. The powders were sintered into ceramics and the dielectric properties of the ceramics were also investigated by LCR meter. The results indicated that alcohol as BaCO3 crystal growth inhibitor promotes the formation of uniform precursors. Neutralized-hydrolysis products are more suitable for the production of fine BaTiO3 powders than self-dissociate products. Pure cubic phase BaTiO3 powders with average particle size 90 nm were synthesized after two hours calcinations at 700 oC. Tetragonal phase BaTiO3 powders prepared at 900 oC can be sintered into ceramics at 1230 oC with relative density 96.1%.The ceramic sintered at 1260 oC showed the best dielectric properties with average grain size 0.95 nm.