Abstract: In order to study the photo-Fenton properties of FeOCl combined with carbon materials, g-C₃N₄/FeOCl nanocomposites were prepared by a simple calcination method according to the different composite mass ratios of g-C₃N₄ and FeCl₃·6H₂O. Composition, structure, and optical properties of the composite samples tested by XRD, SEM, TEM, XPS, UV-vis DRS, EIS, and transient photocurrent testing. The results show that the g-C₃N₄/FeOCl composite has a layered nanorod stacking structure with the good light response and carrier separation capability. When the composite ratio of g-C₃N₄ to FeCl₃·6H₂O is 1∶20, it exhibits excellent photo-Fenton performance, and the degradation rate of rhodamine B (RhB) reaches 92.4%. And after three cycles, the efficiency of the composite material in degrading RhB remains at 80.1% that showing good stability. Based on the experimental results, the Z-type heterojunction between g-C₃N₄ and FeOCl was proposed to improve the separation efficiency of photogenerated carriers, and the possible mechanism of photo-Fenton degradation of RhB by Z-type heterojunction was discussed.