[en] A series of Au-loaded porous g-C₃N₄ nanosheets were prepared by anchoring Au nanoparticles onto g-C₃N₄ surfaces. The as-prepared samples were characterized via x-ray powder diffraction, Fourier transform infrared, transmission electron microscopy, Brunauer–Emmett–Teller, photoluminescence, and ultraviolet–visible measurements, respectively. The activities of Au/g-C₃N₄ composites were evaluated by the photocatalytic degradation of gaseous isopropyl (IPA) under visible-light illumination. The results indicated that 2% Au/g-C₃N₄ exhibited the highest photocatalytic efficiency of gaseous IPA oxidation (11.51 ppm min⁻¹), which was 2.4 times higher than that of pure g-C₃N₄ nanosheets. The remarkable improved photodegradation efficiency derived from the promoted photoinduced carriers separation and larger specific surface area. For one thing, the ultrathin mesoporous g-C₃N₄ nanosheets provided abundant reactive sites and facilitated electron diffusion. For another, the localized surface plasmon resonance and electron–sink effect of Au particles significantly suppress the recombination of the photoinduced holes and electrons. Therefore, the deposition of Au nanoparticles with porous g-C₃N₄ nanosheets could be regarded as an efficient way to enhance the photocatalytic activity of gaseous IPA pollutant removal. (paper)