The method discloses a method for preparing super absorbent resin containing covalent nitrogen by using potato starch as the raw material, which comprises the following main processes: carrying out neutralization reaction between a sodium hydroxide solution and acrylic acid from which polymerization inhibitor is removed under the cooling of ice-water bath; preparing acrylamide into a solution; mixing potato starch with de-ionized water and heating the mixture for pasting; mixing the acrylic acid and the sodium salt solution thereof with the pasted potato starch and the acrylamide solution; adding persulfate, and stirring the mixture under the protection of nitrogen; heating the mixture by water bath to rise the temperature so as to ensure that the potato starch, the acrylamide, the acrylic acid and the sodium salt thereof generate graft copolymerization reaction under the protection of nitrogen; keeping the temperature for 1-2 hours in boiling water bath; baking the products in a baking oven to keep constant weight; and drying the baked products to obtain the super absorbent resin containing covalent nitrogen. Compared with other products on the market, the water absorption of thesuper absorbent resin is multiplied and the super absorbent resin contains nitrogen nutrition elements. The super absorbent resin has great effect on the water conservation, the desert control, the plant growth promotion and the like of soil in dry regions.