The invention discloses a method for improving the quality of silver nitrate. The method comprises the following steps with industrial silver nitrate as a raw material, dissolving the raw material in low-concentration nitric acid; adjusting a pH value by using silver oxide and carrying out extraction by using ether; and allowing an obtained extract to pass through a nonpolar macroporous adsorption resin filled column and carrying out concentration and crystallization so as to obtain silver nitrate with improved quality. The silver nitrate prepared by using the method has purity of more than 99.8 wt% and less than 1 ppm of impurity metal ions, according with the Standard YS-T476-2005 for photographing silver nitrate. According to the invention, ether extraction is effective in removal of iron ions in a silver nitrate solution; organic impurities in the silver nitrate solution can be removed through adsorption with a nonpolar macroporous resin; the product has good quality, and the method is simple to operate, has low energy consumption and is applicable to industrial production.