Photocatalytic technology has broad application prospects in solving environmental pollution associated with rapid international economic growth. ZnO has been widely studied due to its excellent photocatalytic activity, chemical stability, cost effectiveness, high safety, non-toxcity, no second pollution. But, ZnO has a narrow light response range and a low-efficiency utilization of photogenrated charges, which limits its practical application. Different techniques are employed to modify such types of drawback; like doping noble metal (such as; Bi, Ag, Cu, Pt, Au) and non-metal (such as; N, B, C, S,), making shell, morphology engineering, constructing of heterojunction. To enhance the photocatalytic and other applications of ZnO nanoparticles, doping and making core-shell with other noble materials have drawn a great attention. In this work, ZnO core/Bi2O3 shell is synthesized by combining two routes; rapid and sol-gel. The structure, morphology, phase shift, elemental composition, and optical properties of synthesized core-shell nanostructures are characterized by X-ray diffractometery (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transformation infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), UV-VisNIR spectroscopy and also the photo-degradation efficiency evaluated by UVVis spectroscopy. The results illustrated that the synthesized core-shell nanostructures have rod-like in morphology and photocatalytic degradation is enhanced. The photo-degradation efficiency of ZnO-Bi2O3 core-shell nanostructure is evaluated by using methylene blue (MB) and RhB dyes as a pollutant under UV light radiation. The shell material Bi2O3 modified the band gap energy from 3.20 eV to 3.07 eV and surface function of ZnO. Due to this, the photo-degradation efficiency as well as a photocatalytic activity of ZnO nanoparticles is enhanced from 98 % to 100 % and 0.02284 min-1 to 0.04081 min-1, respectively. The photo-degradation efficiency using MB is more enhanced than RhB dye. When the concentration of dye is increased, the photo degradation efficiency is decreased and reverse for increasing of catalyst.