Nd3+ doped g-C3N4 with the diferent content of 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9% and 10% molhave been successfully fabricated by facile chemical method. The crystal structure, absorption spectra, luminescence spectra and photocatalytic activity were investigated through X-ray diffraction (XRD), UV-vis absorption and fluorescence (PL) spectroscopy. The results showed that the Nd3+ impurity was successfully doped into the g-C3N4 crystal, reducing the diffraction intensity and shifting the diffraction peak towards the large 2theta angle. Photoluminescence intensity decreased when doping rare earth Nd3+ and was the smallest for sample CNNd-6 (6mol% of Nd3+). This result is completely consistent with the photocatalytic activity, showing that the sample CNNd-6 has the highest photocatalytic efficiency. The photocatalytic enhancement mechanism is appropriately explained through the model that Nd3+ plays the role of the electron-captured center, reducing the electron-hole recombination rate and increasing the photocatalytic efficiency.