In this study, we showed that the microwave-heated gels have considerably denser network structure compared with water bath- heated gels. We hypothesized that KGM chain stretching in mixed surimi gel was induced by volumetric microwave heating, in contrast to the conductive heating of a water bath. The poly- saccharide network in the gels was distributed homogeneously and formed complex structures. However, no signi cant differences in protein networks were found between the investigated samples. Even though all samples had network structures, the poly- saccharide chains of microwave-heated gels showed a more obvious expansion of the network structure, compared with water bath-treated gels. Microwave treatment may have strengthened gel network and prevented the expanded protein aggregation by long- chain polysaccharide steric effects as well. Additionally, the better WHCs of microwave-heated gels may be due to the stabilization of water/polysaccharide-protein interactions caused by microwave heating. Further investigations are needed in order to elucidate the interaction mechanisms of this newly observed phenomenon.