This study was performed to examine the factors influencing on the degradation of TCE, Benzene and 2,4 DCP in aqueous solution using ultrasonic irradiation. The TCE,Benzene and 2,4 DCP, which are hazard compounds causing environmental pollution, were not decomposable pollutants by convientional treatment. The results shows that the generation of H$_{2}$O$_{2}$, H$^{+}$ and OH$^{-}$ radical was formed by the oxidation and reduction reaction of ultrasound, and then theses decomposed the refractory pollutants of TCE, Benzene & 2,4 DCP in aqueous solution. we conformed that the ultrasonic irradiation was excellent in removal efficiency of the refractory pollutants any other than Advanced Oxidation Processes(AOP), utilized the treatment of organic compounds in the industrial wastewater. Consequently, these results suggest that ultrasonic irradiation may be extremely useful for the treatment of wastewaters contaminated organic pollutants, which is difficult to treat economically by conventional process.