The growth of metal mixed semiconductor particles was known to enhance their photocatalytic properties. In this study, a brand-new and simple one-pot polyol method was successfully used to synthesize metal gold embedded in ZnO nanoparticles (NPs), termed ZnO–Au microspheres. The physicochemical properties of ZnO–Au microspheres were analyzed by X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy measurements, UV–Vis absorption espectroscopy and Fourier transform infrared espectroscopy. Applied to degradation of methylene blue under visible light, the ZnO–Au microspheres photocatalyst showed better photocatalytic activity than pure ZnO NPs. The reusability of ZnO–Au microspheres was also examined.