The invention discloses an absorption method for concentrated nitric acid diluting tail gas. High-temperature nitric acid tail gas produced by concentrated nitric acid dilution is condensed and recycled by using a stainless steel tail gas pipeline for primary absorption; the tail gas discharged through the stainless steel tail gas pipeline then passes through a tail gas absorber and smog-like spraying is performed in the tail gas absorber by sodium hydroxide alkali liquor with weight concentration of 10-14 percent for secondary absorption; and residual tail gas and generated sodium nitrate solution flow blow the liquid level of the alkali liquid in a waste liquid container for tertiary absorption. By using the method, the problems of difficulty in absorption and incomplete absorption of the tail gas produced in the dilution process of the concentrated nitric acid are solved; the absorption rate of the tail gas can reach over 98.5 percent; and the sodium nitrate solution produced by the absorption can be used as a product raw material to be reused.