Electromotive forces of the cells without Liquid-junction, Pt, H-2(g) (p degrees)\HCl (m(E))\AgCl-Ag and Pt, H-2 (g) (p degrees))\HCl (m(?)E), F (m(N))\AgCl-Ag, have been measured at 10 It intervals from 278.15 to 318.15 K, where F stands for D-fructose, m(E) = 0.01-0.1 mol kg(-1), and m(N) = 0.1-0.5 mol kg(-1) The thermodynamic parameters of interaction, g(EN), h(EN), s(EN), and c(p,EN), of D-fructose with HCl in water have been evaluated, together with the standard transfer Gibbs free energies of HCl from water to aqueous D-fructose of various concentrations, In comparison with HCl-D-glucose, the g(HCl-F), h(HCl-F), and s(HCl-F) values are smaller at most of the temperatures. The group additivity analysis was made in detail. The relationship between the hydration and stereochemistry of the sugars was discussed. The suggestion "H+-induced structural changes" was developed and used to interpret the difference in interaction with HCl between D-fructose and D-glucose.