Disintegration of sewage sludge leads to the breakdown of the structure of the sewage floc and release of intracellular fluids. This allows for easy removal of organic compounds that are contained in the cells during further processes of treatment of waste and processing of sludge. One of the methods of disintegration is the use of ultrasound field energy. Depending on the applied process parameters (exposure time, intensity), coagulation or dispersion of the sludge flocs may occur. The aim of the research was to determine the amount of sonication energy supplied to the sludge and the related costs of the disintegration process. The study used digested sewage sludge, which was exposed to ultrasound field energy of different intensity (from 1.6 W/cm2 to 3.8 W/cm2) and exposure time (from 2 to 120s). The sewage sludge sonication process was conducted using Sonics VCX-1500 ultrasonic processor with a maximum output power of 1500W. The vibration frequency of the ultrasound field of the generator was 20 kHz, whereas the maximum wavelength for the 100% amplitude, was 39.42 µm. Energy demand was recorded during each measurement and the amount of sonication energy supplied to the system was calculated relative to dry matter. The experiments showed an increase in the demand for energy along with the extension of the exposure time and the increase in the intensity of the ultrasound field. For two of sludge samples with comparable dry matter content, the sonication energy values were similar.