Ultra-fine grain has high resolution, but the sensitivity is low. We tried chemical sensitization, halogen acceptor, and combination of both, and examined the most suitable sensitization method for ultra-fine grain emulsion. It was got a sensitization effect from even giving processing to immerse a film in to a sodium nitrite solution and succeeded in combination with gold-sulfur sensitization by using this method. A halogen acceptor and chemical sensitization understood that there was additivity in low intensity.