This article is devoted to a qualitative and quantitative evaluation of the permeability values obtained during gas-hydrodynamic well tests with observation well testing in the Turonian deposits of the Yuzhno-Russkoye field. As is well known, Turonian deposits of Western Siberia belong to hard-to-recover reserves. The Turonian reservoir is characterized by low permeability, abnormally high initial reservoir pressure and abnormally low temperature. The obtained data can be used to clarify the geological structure of the field during further development of the deposit. When conducting gas-hydrodynamic studies in the production well, a depth gauge was lowered into the observation well together with hydrostatic listening. The response obtained in the well that was reacting well to stop the well that was perturbing indicates the hydrodynamic connection between the wells. The formula for determining the survey radius was used to calculate the average effective permeability between the wells. When the permeabilities determined according to gas-hydrodynamic studies and observation well testing were compared, it was noted that the data converged. Based on the results, it was decided to carry out gas-hydrodynamic studies together with observation well testing in the future.