The invention provides a method for treating high-concentration nitrate radical wastewater. The specific method comprises the following steps: adding zinc powder and sulfamic acid into the high-concentration nitrate radical wastewater at normal temperature and normal pressure, wherein the mol ratio of nitrate radicals to the zinc powder to the sulfamic acid is 1 to (1 to 5) to (1 to 5); dividing the zinc powder and the sulfamic acid into a plurality of equal parts and adding a medicament for one time every five minutes; adding the sulfamic acid and then adding the zinc powder; sequentially and alternately adding within two hours; after adding the materials, reacting for 2 to 5 hours. Compared with the prior art, reagents used by wastewater treatment are cheap and convenient to purchase; wastewater treatment equipment does not need to be additionally purchased and initial concentration of NO3<-> in the wastewater is in a range of 5000mg/L to 50000mg/L; the concentration of the NO3<-> in the wastewater treated by the method is smaller than or equal to 15mg/L (shown as figure 1) and the wastewater meets direction emission standards of the NO3<-> of Emission Standard of Pollutants for Copper, Nickel and Cobalt Industry. Meanwhile, an alternate adding manner of the sulfamic acid and the zinc powder is adopted, so that the capability of treating the nitrate radicals in the wastewater of the whole method is enhanced.