By mixing boronic acid-modified poly(acrylic acid) (pAA-BA) and beta-1,3-glucan Schizophyllan (SPG) in water at pH 9.9, hydrogel was readily formed with the aid of the sugar and boronic acid interaction. This hydrogel showed the reversible transformation between sol and gel depending on the medium pH. Moreover, this hydrogel stability was sensitive to fructose concentration. As one potential output, we prepared the hydrogel including single-walled carbon nanotubes, utilizing the nanotube-wrapping property inherent to SPG.