A new aqueous sol was synthesized to prepare Ag-doped TiO2/Ti composite tight ultrafiltration (UF) membranes. This sol was prepared based on water (> 95 wt%), for which the hydrodynamic size of 8 nm could be obtained by tuning the electrostatic and steric repulsive forces, breaking the limit of the polymeric sol-gel method to prepare tight UF membranes. For the preparation of the sol, high water content can significantly reduce the use of organic solvents and is more environment-benign. Moreover, Ag doping can considerably improve the toughness of the supported membranes to efficiently prevent the TiO2/Ti composite membranes from cracking and overcome the thermal expansion mismatch of ceramic membranes and their metallic supports. The prepared Ag-doped TiO2/Ti composite membranes presented a molecular weight cut-off of 3 kDa with a pure water flux of 24 L m(-2) h(-1) bar(-1) and exhibited good dye removal capabilities. The proposed Ag doping method has considerable potential for the fabrication of integrated hybrid ceramic-metallic composite membranes.