Abstract: Abstract:KGM (konjac glucomannan) is a water-soluble and high-molecular-weight polysaccharide extracted from the roots of Amorphophallus Kojac plant. D-glucose and D-mannose are bonded by β-1,4 pyranoside bonding, and therefore, KGM is hard to be digested by the human. Due to the unique characteristic, KGM has been applied to a wide range of products as nutritional supplements for constipation, obesity, high cholesterol, acne vulgaris and type 2 diabetes. KGM often serves as emulsifier or thickener in food or pharmaceutical industries, however, thickening effect of KGM is not strong enough for products requires. The synergistic effect has been reported between the KGM and carrageenan or xanthan gum (XG), and thickening effect of KGM could be greatly enhanced once the XG or carrageenan has been added. XG is popularized for its outstanding thickening effect and synergistical effect with other polysaccharides. It is interesting to find that these 2 kinds of non-gelling or weak gelling polysaccharides could gel at low concentration once they were mixed. Several factors including pH value, temperature and salt concentration affect the properties of KGM-XG mixed gel. Investigation on the regulatory mechanism of salt on the dynamic rheology properties of KGM-XG mixed gel has been conducted in this paper. Different concentration of salt ranging from 1 to 15 mmol/L was added into the KGM-XG mixed gel respectively, and the dynamic rheological properties were measured through strain sweep, stress sweep, frequency sweep, temperature sweep, creep-recovery test. Results show that the addition of salt will compromise the steric net structure, and Na+ will screen the electrostatic repulsion of XG and lead to the ordering of XG molecular conformation, thus weakening the crosslinking between XG and KGM. Actually, KGM combines XG through hydrogen bonds, since KGM is in disordered state, and synergistic effect between XG and KGM is on the basis of massive hydrogen bonds, some of the bonds are on the backbone of XG, while some of the bonds are on the side chain. The ordering of XG actually decreases the binding sites of KGM, and therefore, elasticity properties of the mixed gel system decrease with the increasing salt concentration and the storage module representing the elastic property decreases, too. Stress sweep and strain sweep indicate the strain range of linear viscoelastic region is 0.01%-30%; increasing the strain, the inner structure of KGM-XG mixed gel system will be irreversibly destroyed. Elevating salt concentration will decrease the gel/sol transition temperature since the salt has changed the crosslink ways of KGM with XG. Ca2+ possess higher valence states, and therefore, the effect for weakening the gelling properties of KGM-XG is stronger compared to that of Na+ added in gel at low concentration. Nevertheless, the situation becomes different once the concentration of Ca2+ reaches 10 mmol/L, and frequency sweep indicates that the Ca2+ might promote the cross-links between XG molecules and therefore lead to the increased of storage module compared with low Ca2+ concentrations. According to Burger's model for creep-recovery test, the results can provide quantitative evidence to the viscoelastic properties of KGM-XG mixed gel, and the mechanism involved.