NOVELTY - An ultrafine spherical silver powder is prepared by dissolving silver nitrate in deionized water to obtain 2.5-5 mol/L silver nitrate solution, adding 25 mass% aqueous ammonia, stirring to react at 10-30 degrees C and obtain 1.2-3 mol/L silver ammonia complex in which molar ratio of silver nitrate:ammonia is 1:2-6, dissolving anhydrous sodium sulfite in deionized water, adding p-aminophenol reducing agent and organic dispersant in which molar ratio of p-aminophenol:sodium sulfite:organic dispersant is 1:0.3-1:0-0.2, and stirring to obtain 0.5-2 mol/L aqueous reducing agent solution.    USE - Preparation of ultrafine spherical silver powder for solar cell or electronic touch screen with conductive silver paste material.    ADVANTAGE - Preparation process is simple, easy to control, safe, and environment-friendly. Product has high purity.    DETAILED DESCRIPTION - An ultrafine spherical silver powder is prepared by dissolving silver nitrate in deionized water to obtain 2.5-5 mol/L silver nitrate solution, adding 25 mass% aqueous ammonia, stirring to react at 10-30 degrees C and obtain 1.2-3 mol/L silver ammonia complex in which molar ratio of silver nitrate:ammonia is 1:2-6, dissolving anhydrous sodium sulfite in deionized water, adding p-aminophenol reducing agent and organic dispersant in which molar ratio of p-aminophenol:sodium sulfite:organic dispersant is 1:0.3-1:0-0.2, stirring to obtain 0.5-2 mol/L aqueous reducing agent solution, adding silver ammonia complex and aqueous reducing agent solution at 10-30 degrees C for 5-10 s in which molar ratio of silver ammonia complex:p-aminophenol is 1:0.5-0.55 and pH of reaction solution is 10-11, stirring to precipitate silver particles for 3 minutes, adding 0.1-1 mass% amino silicone oil or hydroxy silicone oil, stirring for 15 minutes to adsorb surface and obtain silver powder, filtering to isolate silver powder, washing with water and ethanol respectively, and drying at 80 degrees C to obtain ultrafine spherical silver powder with average particle size of 1-3 mu m, tap density of 4-5 g/cm3, and specific surface area of 0.4-1 m2/g.