Abstract: Provided is a method for preparing an aqueous dispersion of metal nanoparticles having superior dispersibility and being sinterable at low temperature by modifying the surface of metal nanoparticles having hydrophobic groups with hydrophilic groups. Specifically, by treating the surface hydrophobic groups of the metal nanoparticles with a surface modification solution containing a surfactant and a wetting-dispersing agent, the treatment throughput can be improved about 10-fold and the particles can be monodispersed without agglomeration. Further, by using an antioxidant and a ligand removal agent in the solution, denaturation and oxidation of the particles can be prevented and the high-boiling-point hydrophobic ligands can be eliminated effectively. The hydrophilically treated metal nanoparticles may be dispersed in an aqueous-based solvent to prepare a metal ink sinterable at low temperature.