This study investigated the combined application of nitrogen and sulfur fertilizers on the structural characteristics and physicochemical properties of buckwheat resistant starch. The results showed that combined fertilization did not change the crystalline diffraction pattern of the resistant starch samples (exhibiting a B-type crystalline structure), but significantly (p <
0.05) increased the relative crystallinity (35.07-44.36 %). In addition, combined fertilization enhanced resistant starch content (28.36-35.22 %), apparent amylose content (20.50-35.06 %), particle size, pasting temperature (50.30-50.66 °C) and gelatinization enthalpy (2.77-4.65 J g