The graphitic carbon nitride(g-C3N4) is found to be an efficient photocatalyst for the reductive degradation of decabromodiphenyl ether(BDE209) under UV irradiation(>360 nm).g-C3N4 was prepared by heating dicyandiamide.X-ray diffraction,X-ray photoelectron spectroscopy,and UV-vis spectra were used to characterize the properties of as-prepared catalysts.The photoreductive degradation kinetics of BDE209 was further investigated under different reaction conditions.The degradation of BDE209 is a stepwise process,and the bromines at meta positions are much more susceptible to remove than those at the ortho and para positions.A possible photoreductive mechanism was also proposed. The graphitic carbon nitride (g-C3N4) was found to be an efficient photocatalyst for the reductive degradation of decabromodiphenyl ether (BDE209) under UV irradiation (> 360 nm). G-C3N4 was prepared by heating dicyandiamide.X-ray diffraction, X -ray photoelectron spectroscopy, and UV-vis spectra were used to characterize the properties of as-prepared catalysts. The photoreductive degradation kinetics of BDE 209 was further investigated under different reaction conditions. The degradation of BDE 209 is a stepwise process, and the bromines at meta positions are much more susceptible to remove than those at the ortho and para positions. A possible photoreductive mechanism was also proposed.