Cavitation jets with frequency in the range from 400 Hz to 1 MHz exert a strong action on the rate of various physical and chemical processes. In the literature cavitation effects are described used in the processes of cleaning, dispergation, homogenization, crystallization, etc. Ultrasonic cavitation is used in the food industry, în particular, for extraction of bioactive substances from vegetable raw materials.   This work refers to the utilization of effects of ultrasonic cavitation – action of acustic microjets, sonic pressure, and capillary effect - for the investigation of the extraction process of tomatoside from tomato seeds with the aim to reduce the process duration. An ultrasonic cavitaţion installation was designed and manufactured, which consists of an ultrasonic bath with a thermostat for temperature regulation. The energy introduced in the processed material was controlled by variation of the amplitude of ultrasonic waves up to the value of 40 mm. The composition of tomatoside was determined according to the mass of the extracted substance and by chromatographic method. Dry tomato seeds were loaded in an ultrasonic bath with distilled water in the mass ratio of 1 : 3. The mixture was heated up to 45-50 ^oC and subjected to the action of ultrasonic cavitation; the process without sonication was performed at 100 ^oC. The mass and composition of the extracted tomatoside were determined.   The analysis of the results shows the following (Figure a, b):  - processing of tomato seeds with ultrasonic cavitation microjets reduces the extraction duration of tomatoside by a factor of 8–9; the process temperature decreases from 100 to 45–50 ^oC. For the process duration exceeding 60 min the tomatoside mass decreases. The entire quantity of the tomatoside contained in tomato seeds is extracted virtually in the first 10 – 15 minutes of the ultrasonic cavitaţion processing. In the conventional extraction method this can be obtained after soaking of the seeds during about 48 hours;  - increasing of the amplitude of ultrasonic oscillations leads to the respective increasing of the power of the acoustic microjets initiated by ultrasonic cavitation. The mass of the extracted tomatoside exhibits maximum at the amplitide of 20–25 mm (Figure, a). This shows that the power and speed of microjets are so large, that they circulate around the cells and cannot penertrate the cell capillaries.  The process acceleration occurs since the sonic pressure and acoustic microjets initiated during the implosion of cavitation bubbles generate a capillary sonic effect. This leads to acceleration of the solvent diffusion in the cell walls and the swelling of the seeds (their cells). Then the destruction of seeds occurs, extraction of tomatoside from the cells and its dissolution in the solvent.