Cellulose-based Ultraviolet B (UVB)-shielding films were prepared by coating SnO₂ film onto regenerated cellulose (RGC) film through a magnetron sputtering method. The dependence of the crystalline quality and optical property of the SnO₂ film on the sputtering power was systematically studied. High quality SnO₂ film was grown on RGC film at an optimum sputtering power of 150 W. The optical properties of the composite film can be tailored by adjusting the thickness of the SnO₂ film. The SnO₂/RGC composite film exhibited high visible transparency and excellent UVB-shielding capacity, which can be used for protection against short-wave radiation.