The degradation of environmental contaminants with photocatalysts has bright prospects for application in the control of pollution. In this study, BiOBr/ZnO/WO3 heterojunctions have been documented to be reliable visible-light photocatalysts for phenol deterioration. X-ray diffraction, X-ray photoelectron spectroscopy, Fourier-transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, photoluminescence spectral analysis, electrochemical impedance spectroscopy (EIS), EIS Bode plots, linear sweep voltammetry, and UV-visible diffuse reflectance spectroscopy were employed to describe the heterojunction’s structure in addition to its optical features. The results revealed that the BiOBr/ZnO/WO3 ternary photocatalyst displayed more degradation activity in comparison to single-phase ZnO, WO3, or BiOBr, which is also higher than that of binary mixture photocatalysts with a phenol degradation efficiency of 90%. The influence of degradation variables, for instance, the potential of hydrogen (pH) and the initial organic contaminant content besides the heterojunction dose, on the deterioration efficiency was optimized using the response surface methodology. The degradation efficiency reached 95% under the optimal conditions of 0.08 g/0.03 L catalyst dose, a pH of 9, and an initial organic contaminant content of 10 mg L-1. However, the optimal phenol degradation efficiency of 39.37 mg g-1 was achieved under the conditions of 0.08 g/0.03 L catalyst dose, pH of 9, and 200 mg L-1 initial phenol concentration.