As an alternative to conventional electroplating, we propose TSV filling using the electrophoresis of metal nanoparticles. Colloidal solution of Ag nanoparticles having a high zeta potential has been designed and made up. Via holes for the test experiment were prepared in a photoresist layer on a Au film which acts as anode. Ag nanoparticles were completely filled into the cavities of depth of 30 μm and diameter of 10 μm within one minute. After annealing at 250 °C, the electric conductivity was 1.57 × 10-5 [ω·cm]. These results demonstrate the potentials of the application of electrophoresis of metal nanoparticles to high speed TSV filling.