A new type of Ag/AgCl/g-C3N4 composite could be facilely fabricated. The techniques of X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), UV-vis diffuse reflectance spectroscopy (DRS), Fourier transform infrared spectra (FT-IR) were used to characterize the phase and structure of the samples. The activity of the Ag/AgCl/g-C3N4 composites for photodegradation of methyl orange (MO) was higher than that of either the pure g-C3N4 or Ag/AgCl. DRS of Ag/AgCl/g-C3N4 composites exhibited strong absorbance in the visible region due to the localized surface plasmon resonance (LSPR) absorption of metal Ag nanomaterial. The enhancement of photocatalytic activity of the Ag/AgCI/g-C3N4 composites was attributed to the effective charge transfer from plasmon-excited Ag to AgCI, which suppressed the charge recombination during photocatalytic reaction process.