This study presents the effects of dry heat (DH) assisted by pre-and post-electron beam (EB) treatment on buckwheat starch's multiscale structural, physicochemical, and digestive properties. The granule integrity and crystal shape were not affected by the investigated treatments. However, DH and EB treatments decreased amylose content, crystallinity, molecular weight, swelling power, thermal transition temperatures and gelatinization enthalpy while increasing solubility and the content of A chain, B1 chain, and resistant starch. EB application to DH starch promoted subsequent structural changes and enhanced starch properties compared to samples DH-processed alone. In addition, EB-induced starch chain depolymerization and structural rearrangement had sequential effects. EB pre-treatment reduced DH starch's amylose content, molecular weight, and swelling power while enhancing the content of A- chain, rapidly digestible starch, and resistant starch compared with EB post-treatment. This innovative study provides a theoretical basis for the potential applicability of EB irradiation in modifying the properties of DH starch.