In this study, the application of adsorption processes on the surface of TiO₂ nanoparticles and oxidation by O₃, UV, O₃/TiO₂, and the UV/TiO₂ in the removal of reactive red 198 dye form textile wastewater was examined. Then, Analytical Hierarchy Process (AHP) was used to choose the best removal method. The studied criteria for decision-making in selecting the best choice included the rate of dye removal in different situations, with the sub-criteria of studied variables, cost, with the sub-criteria of initial operation and maintenance cost, and the required expertise to use each method. Grading and preference of each method were calculated based on the efficiency of removal in different conditions, the price of each tool in the market, and the consumed energy of each method. The UV/TiO₂ process was considered as the best-known method based on AHP model. Results indicated that this model can be a useful and suitable tool for policy-makers and decision-makers to choose the best treatment process in different conditions.