Abstract: Application of ultrasonic irradiation for inactivation of nematodes was investigated. Experiments show that it is possible to decrease the number of organisms present in the water and that the process depends on exposure time, frequency and intensity of the ultrasound irradiation, as well as on the type of organisms. As it is considered by 2, 4, 6, 8 ,10 and 12 min of sonication about 23.75, 42.50, 53.5, 82.25, 89.25 and 100% of the adult present are destroyed, respectively. But by 2, 4, 6 and 8 min of sonication about 38.0, 50.5, 58.75 and 100% of the larva present are destroyed, respectively. The results using Bransonic bath at 42 kHz (155 W input power) show that using this frequency it would appear that 100% of the nematodes adult and larva are destroyed in 12 and 8 min, respectively.