The invention discloses a method for a double-parent potassium-containing super absorbent resin. The method mainly comprises the following process steps of: under the cooling action of an ice-water bath, performing a neutralization reaction on solution of potassium hydroxide and acrylic acid from which a polymerization inhibitor is removed; mixing carboxymethyl starch, starch phosphate and deionized water; adding the acrylic acid and sylvite solution thereof, potassium persulfate serving as an initiator and solution of N,N'-methylene bisacrylamide serving as a cross-linking agent; stirring under the protection of nitrogen gas and heating in a water bath so as to perform graft polymerization on the carboxymethyl starch, the starch phosphate, the acrylic acid and sylvite thereof; and reacting while preserving heat, drying and grinding so as to obtain the double-parent potassium-containing super absorbent resin taking the carboxymethyl starch and the starch phosphate as raw materials. The super absorbent resin prepared by the method has high water absorption, contains nutrient elements such as potassium and phosphorus and has wide application prospect in the aspects of water conservation of soil, desertification control, promotion of plant growth and the like.