At the present stage, the development of the oil and gas industry of the Russian Federation is impossible without replenishing the resource base, and therefore an urgent task is to conduct research, prospecting and evaluating petroleum potential in undiscovered areas of fields. The aim of the study is to conduct a comprehensive assessment of the reservoir of the productive formation of the Kanevskoye field. We have carried out mineralogical and petrographic studies, laboratory studies to assess the effective porosity of the core sample by the saturation method, particle size analysis, X-ray diffraction analysis. Our studies have shown that the considered initial sands under consideration, which formed the reservoir rocks of the productive horizon of the Kanevskoye field, were formed by coastal or beach type marine sediments. This is confirmed by the poorly rounded shape of the grains and the presence of glauconite in the rocks. The studied core sample is a fine-grained glauconite-feldspar-quartz sandstone with an admixture of aleurite fraction, with semi-rounded grains, pelitic cement, basal and porous-basal, silt-psammitic structure. The total porosity is 14.3 %. A comprehensive assessment of the reservoir of the productive formation of the Kanevskoye field has been carried out. The reservoir is productive. Therefore, it is necessary to make a project for conducting geological exploration.