The colors present in the effluent from dyeing and textile plants are one of the most dangerous sources of environmental pollution due to their toxicity and carcinogenesis. Dye removal is, therefore, necessary to prevent their discharge into the environment. A number of methods are available for dye removal from industrial effluents, among which Fenton/Ultrasonic oxidation process is an effective one due to its high efficiency in color removal. The objective of this pilot-scale experimental study was to investigate the operational parameters involved in the removal of Reactive Red 2 dye (RR2) using the Fenton/Ultrasonic process and its efficiency. Theeffects of pH, H2O2, and Fe2+ were evaluated using an ultrasonic reactor at 40 KHz with a power of 100W. Once the parameters had been optimized, the effects of temperature, mixing speed, and different dye concentrations on the Fenton/Ultrasonic process efficiency were measured. The optimal parameters of pH, hydrogen peroxide, and ferrous ion concentration in the were determined to be 3, 2, and 0.2 mmole, respectively, in 45 minutes so that a removal efficiency of 98.91% was obtained for an optimum hydrogen peroxide to ferrous ion ratio of 10. The results indicated that the Fenton process has a good performance in the removal of Reactive Red 2.