Disclosed is a metallic ink, a method of forming electrodes using the metallic ink, and a substrate using the metallic ink. The metallic ink comprises at least one oxide selected from metal oxide nanoparticles and partially polycondensated metal oxides having a size of 100 nm or less, and metal nanoparticles having a size of 100 nm or less. The oxides and the metal nanoparticles are dispersed as isolated ultrafine particles in solvent. The method comprises patterning the ink using an inkjet printer to form a conductive wire. The substrate is produced through the method. It is thereby possible to conduct patterning using an inkjet printer, and adhesive power to substrates is improved. The metallic ink is useful to produce electrodes of various panels, such as PDPs.