Samples of carbon-rich rocks from domanik deposits and the oil-water contact zone of the Bavly field of the Republic of Tatarstan (Russia), as well as extracts from them, have been studied by thermal analysis, IR and EPR spectroscopy, and gas-liquid chromatography. Significant differences have been revealed in the chemical composition and physicochemical properties of both soluble and insoluble organic matter from various areas of the Bavly field. Compared with bitumens from the oil-water contact zone, bitumoids from domanik deposits are heavier; they are enriched in oxidized structures and contain elevated levels of isoprenoid hydrocarbons and light normal alkanes. Bitumoid asphaltenes are enriched in sulfur and nitrogen, depleted in oxygen, and characterized by an increased concentration of paramagnetic centers. These differences have to be taken into account when testing technologies for the development of domanik deposits.