Hydraulic fracturing is the main method of intensifying hydrocarbon production, and its role increases with the transition to the development of hard-to-recover reserves, deposits in shale rocks, Bazhenov and Domanik formations. The complexity of the technology of hydraulic fracturing imposes requirements for the complexity of the calculation models used in the planning and execution of works. Verification of the validity of the assumptions used in theoretical models is possible only by conducting controlled experiments under laboratory conditions. In these experiments, it is important to use measurement methods that do not affect the process under study, on the one hand, and allow you to get the maximum information, on the other hand. For several years, the project team has been conducting an experimental study of hydraulic fracturing on the original installation, which allows working under three-axis loading conditions on cylindrical samples with a sufficiently large diameter (430 mm) and a height of 70 mm. In the last experiments, we used ultrasonic transmission of samples during the formation of hydraulic fracturing and filling it with liquid. Interesting results were obtained that require the development of this method and its testing in special experiments with a controlled opening aperture of hydraulic fracturing cracks, controlled filling of it with liquid, controlled contact area between the sides of the crack when it is not fully closed. The influence of the above facts on the parameters of ultrasonic pulses passing through the crack will be studied. The proposed method will also allow us to determine the possibility of the formation of" bridges " of intact rock, which can occur during the formation of a three-dimensional crack. Along with the experiments, it is proposed to calculate the passage of elastic waves through cracks with incomplete destruction of the material and different liquid filling.