The paper presents the results of microtomographic studies of filtration and storage properties of highly permeable reservoir rocks for underground gas storage (UGS) using methods of digital analysis of computed tomography (CT) data. The studies were carried out on a high-resolution micro-CT scanner ProCon X-Ray CT-MINI. Methods of non-destructive analysis of internal structure of highly porous rocks and modeling of hydrodynamic processes by means of GeoDict software are presented. Structural heterogeneity and fracturing of rocks were evaluated. 3D models of specimen internal space were created on the basis of multi-scale images. Numerical modeling of filtration processes in the obtained structures within the Stokes approximation for three selected mutually perpendicular directions in the rock was carried out. The values of open and closed porosity, geodesic tortuosity were calculated, and the characteristics of percolation paths in the rocks under study were analyzed. The spatial distribution of porosity in the rocks was studied. It was shown that there is no pronounced dependence of changes in filtration properties in the selected directions on the quantitative characteristics of void space. The conclusion about the degree of anisotropy of filtration and capacitance properties was made. The filtration characteristics calculated as a result of numerical analysis were compared with experimentally obtained laboratory values. The results of the study are intended to expand existing approaches to non-destructive analysis of UGS core material and can be used to create and refine geomechanical models of UGSs, integral assessment of reservoir property and development of operational recommendations.