The invention discloses a method for preparing peanut peptides through the step enzymatic hydrolysis of peanut protein isolate by using two neutral proteases. The method comprises the following steps: 1, dissolving peanut protein isolate powder in water to obtain a peanut protein isolate solution, and maintaining the peanut protein isolate solution in a 80-85DEG C water bath for 10-15min; 2, taking out the peanut protein isolate solution processed in step 1, and adding a neutral protease when the temperature of the peanut protein isolate solution drops to a temperature suitable for the enzymatic hydrolysis of the neutral protease to obtain an enzymatic hydrolysate recorded as a first enzymatic hydrolysate; 3, adding a composite protease to the first enzymatic hydrolysate, and continuously carrying out enzymatic hydrolysis to obtain a second enzymatic hydrolysate; and 4, inactivating the neutral protease and the composite protease in the second enzymatic hydrolysate, centrifuging, taking the obtained supernatant, and carrying out spray drying of the supernatant to obtain the peanut peptides. The method allows the yield and the purity of the peanut peptides to be high, the molecular weights of the peanut peptides to be below 1000Da in a concentrated manner and the peanut peptides to have a strong ACE inhibition activity, and has the advantages of low preparation cost, short preparation time, simple preparation method, mild preparation conditions and the like.