Sagittaria sagittifolia, Eleocharis dulcis and Trapa natans are chief aquatic rhizomatous crops in southern China. Their proper combination can create novel food products with new texture and nutritional values. In the paper, mixture design approach was used to investigate the effects of the composition of these three starches on the textural properties of gels, and to characterize the gelatinization process of different starch blends ratio by using differential scanning calorimetry (DSC). The results showed that the mixture starches presented antagonistic effect for Sagittaria sagittifolia starch and synergistic effect for Trapa natans starch. These two actions interacted and finally displayed the antagonistic effect on hardness, cohesiveness, elasticity, consistency and chewiness, but not on adhesiveness. The DSC results indicated that components of the mixture dependently gelatinized, as evidenced by the two endothermic peaks corresponding to the individual components. The starches of Sagittaria sagittifolia and Eleocharis dulcis inhibited the recovery of Trapa natans starch, which led to less swelling of the starch granules. The research can provide a reference for efficient use of special starches from southern China.