Through Fourier infrared spectrometer (FT-IR), rheometer, texture analyzer, low-field nuclear magnetic resonance (LF-NMR) and differential calorimetry scanner (DSC), used corn starch as raw material, the aging and water migration of corn starch with different content of soy isoflavones was analyzed the impact of characteristics. The results showed that the starch aging degree deepened during the storage period. After adding soy isoflavones, the change rate of the elastic modulus of starch gel was reduced, and the short-term aging of corn starch was delayed. With the same storage period, as the concentration of soy isoflavones increased, the starch retrogradation rate decreased significantly; the hardness value decreased, the gel texture was softer; the hydrogen bond absorption peak was red-shifted, the values at R1047/1022 and R995/1022 gradually decreased, and the relative degree of order decreased; the content of bound water and non-flowing water increased, and the free water content decreased. Soy isoflavones could effectively inhibit the long-term aging of starch, the study could provide basic data on the effect of flavonoids on starch retrogradation properties.