Objective To investigate the effects of structural changes in Cyperus esculentus starch on its apparent viscosity, water absorption index, and stability, providing theoretical support for its development and application in blended powders.Methods C. esculentus powder was modified by three methods, i.e., ultrafine grinding, microwave treatment, and enzymatic treatment. The effects of starch structure changes caused by these modifications on powder dispersibility were analyzed.Results Compared with native C. esculentus powder, enzymatic treatment reduced the relative crystallinity from 43.49% to 20.69%, causing the most significant starch structure disruption and notably improving dispersibility. The apparent viscosity and stability of the powder dispersion increased significantly, and the water absorption index and water solubility index increased by 34.39% and 100.03%, respectively. Microwave treatment caused aggregation of starch molecules, reduced relative crystallinity to 30.55%, and slightly improved dispersibility, as indicated by increased apparent viscosity, stability, centrifugal sedimentation rate, and water absorption index by 1.30% and 12.10%, respectively. Ultrafine grinding had the least effect on starch structure, with relative crystallinity decreasing to 37.41%, but apparent viscosity, stability, and water absorption index all decreased, which was unfavorable for dispersibility improvement.Conclusion Ultrafine grinding, microwave treatment, and enzymatic treatment all induced structural changes in C. esculentus starch, thereby affecting powder dispersibility, with enzymatic treatment showing the most significant effect.