Three different methods (ultrasonic dispersion, hydrothermal method and calcination) were used to prepared g-C ₃N ₄/WO ₃  heterojunctions. Obtained catalysts were characterized with X-ray diffraction (XRD), UVvis spectroscopy, nitrogen adsorption, X-ray photoelectron spectroscopy (XPS), photoluminescence (PL), and Electrochemical impedance spectroscopy (EIS). The results showed that the interaction between g-C ₃N ₄/WO ₃  and WO ₃ was obviously affected by the preparation methods, resulting in the significant difference in separation rate of photogenerated electrons and holes. The photocatalytic performances were detected in photocatalytic Rhodamine B (RhB) degradation under simulated visible light. The results indicated that activities of g-C ₃N ₄/WO ₃  heterojunction composites were evidently higher than that of single g-C ₃N ₄/WO ₃  or WO ₃ semiconductor, and the heterojunction semiconductor prepared by the hydrothermal method showed the highest photocatalytic activity.