Glutathione (GSH) is an important biochemical substance in the body, and efficient detection plays an important role in evaluating human health. This work develops a simple and efficient method for GSH detection by biomimetic enzyme-catalyzed colorimetric sensing. A novel scandium oxide crystal is prepared by a one-step pyrolysis method. The crystal structure, microstructure, and surface potential of scandium oxide crystals are analyzed by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and potentiometry. Furthermore, the scandium oxide crystal can catalyze the oxidation of the colorimetric substrate TMB in the presence of H