S-scheme heterojunction has been extensively investigated for hydrogen evolution and environmental pollution issues. In this study, a monoclinic WO₃/hydrothermally treated red phosphorus (HRP) S-scheme composite was prepared by hydrothermal method. XPS and EPR characterization confirmed that the monoclinic WO₃/HRP composite formed S-scheme heterojunction. 5%WO₃/HRP composite displayed the optimal photocatalytic activity under visible light irradiation, and its degradation rate of Rhodamine B (RhB) reached 97.6% after 4 min of visible light irradiation, while its hydrogen evolution rate reached 870.69 μmol·h^-1·g^-1 which was 3.62 times of that of pure HRP. This could be ascribed to the tight interfacial bonding between WO₃ and HRP, and the formation of S-scheme heterostructure, enabling rapid separation of photogenerated carriers and therefore improving the strong redox capacity. This study provided a promising RP-based photocatalyst to meet the demand for clean energy and drinking water.