The ultrasound techniques have employed to study the effect of high frequency on the degradation of methyl orange dye, MOD, from a model of industrial wastewater. Three different initial concentrations of methyl orange (10, 30 and 50 ppm), with three different power supply's to ultrasound device voltages (15,20 and 25 V), and two different liquid volumes (15 and 20 ml) were investigated here on the effect of MOD degradation. Results show that as the concentration of azo dyes increases, the degradation increases. It was also found that as the liquid volume increases, the ability to degraded azo dyes decreases. The best condition achieved for degradation of azo dyes obtained at 50 ppm, 15 ml, and 25 V. The degradation data results are best fitted with a first order kinetic degradation model. The degradation rate constant was calculated by best fitting and found to be equal to an average value for 25 and 20 V to 0.0114 min(-1). (C) 2014 Elsevier B.V. All rights reserved.