We attempted to fabricate metal/dielectrics composite capacitors exhibiting high effective dielectric constant by a low-temperature wet chemical approach. The green compacts consisting of Ti metal particles, BaTiO₃ fillers, and TiO₂ precursor nanoparticles were successfully converted into Ti/BaTiO₃ composite compacts by the hydrothermal method at 160°C. The effective dielectric constant of these composites tends to increase with the Ti metal content and jumped up to over 10³ near the percolation threshold. When we used the Ti(core)–BaTiO₃(shell) particles as the metal component, the thin BaTiO₃ shell layers covering on the Ti particles prevented the direct contact among metal particles and increases the percolation threshold. Since the effective dielectric constant of these composites depends largely on the dielectric properties of the BaTiO₃ layers, it is important to control the microstructure of these composites to improve the dielectric properties of such composites.