［Objective］ This study aimed to investigate the effects of cross -linking,cross -linking oxidation and cross -linking oxidative acetylation on the physicochemical properties of arrowhead starch.［Methods］ Arrowhead starch was modified using epichlorohydrin as cross -linking agent,hydrogen peroxide as oxidizing agent,and acetic anhydride as acetylation agentto produce cross -linked starch,cross -linked oxidative starch,and cross -linked oxidative acetylation starch.The physicochemical and structural properties of these modified starches were analyzed.［Results］］ All three modified starches exhibited a type A crystalline structure with improved thermal stability.Crystallinity decreased by 1.93%,while the ratio of 1 047 cm-1/1 022 cm-1 increased,indicating a more ordered starch structure.Cross -linking oxidation enhanced the transparency and solubility of the starch,achieving the highest crystallinity among the modifications.Infrared spectroscopy revealed distinct C —O bonds associated with primary/secondary alcohol hydroxyl group at 1 011 cm-1 and the C—O—C stretching vibration of the glucoside bond at 857 cm-1 were very obvious.After acetylation,the coagulability,solubility of cross -linked oxidized starch were significantly improved,the crystallinity decreased by 24.91%,and the ratio of 1 047 cm-1/1 022 cm-1 declined,reflecting a reduction in structural order.［Conclusion］ Compound modification techniques can significantly enhance the quality of arrowhead starch.The appropriate modification method can be selected based on specific application requirements.