The conformation of oxidized scleroglucan (sclerox) was characterized in water and in NaCl aqueous solution by means of small-angle X-ray scattering (SAXS). The observed SAXS profiles were analyzed in terms of a modified broken rod model, where each rod component was replaced with the molecular models of a triple-stranded helix and a single chain simulated by the Monte Carlo method. The electrostatic interaction due to carboxylate groups was taken into account by assuming a Gaussian-type interaction potential. The results confirmed that the triple-stranded helix of scleroglucan was disentangled to a single chain by the oxidation of beta-D-glucosyl side residues, The triple-stranded structure is partly recovered by shielding charge on the side chains.