The object of research: ultrasonic processing technology of textile materials. Investigated problem: increasing the degree of splitting of complex hemp fibers due to the effect of the mechanism of ultrasonic cavitation on them. The main scientific results: The article shows the potential of textile production to ensure the environmental friendliness of textile products, and the development and implementation of new eco-technologies of physical and mechanical cottonization of hemp fiber is important in this. Analysis of existing methods of cottonization and structural features of hemp fibers has led to the conclusion that the destruction of cellulose satellites in complex fiber can be considered as a process of purification from impurities, since the technologies for purification of substances in the aquatic environment by ultrasound now are widely used. Therefore the process of cottonization of hemp by technology of ultrasonic treatment was used in this investigation for the first time. The basic principle effect on the textile material what placed in the liquid are the hydroacoustic effects formed by the collapse of cavitation bubbles in the contact zone "liquid-material". Experimental studies of the geometric characteristics of the obtained hemp cottonine were carried out, and the effectiveness of the effect of ultrasonic vibrations on the change of the structure of hemp fiber was confirmed. Due to the removal of inlaid substances under the action of cavitation, the complex fibers of hemp were split, as a result of which the range of variation and the absolute value of their length and linear density were decreased. The scope of practical use of the research results: textile enterprises of deep processing of bast raw materials into technical and household yarns. Innovation technological product: technology of ultrasonic cottonization of hemp fibers. The scope of using the innovation technological product: manufacturing of textile hemp products for general use.