The article analyses policies of the world largest oil and gas companies to integrate blockchain into their business structure. It is revealed that super-majors and majors concentrate mainly on digitalization of the hydrocarbons trade and trade financing. The multilateral alliances, involving the oil and gas companies, banks and oil traders, have been established in order to implement that goal. Recently partnerships for testing blockchain use in the relatively easily digitalized oil operations and actives were launched. European supermajors BP и Royal Dutch Shell within their strategies actively experiment with possibility to increase the business profitability through using blockchain at all stages of value added creation. The analyses allowed to conclude that projects to inbuilt blockchain into the business models of oil and gas companies remain so far at the transitionary phase from the proof-of-concept stage to that of the market implementation. Large scale enterprise use of blockchain one has to expect from the middle of the 2020-s. Oil and gas companies who will be the first to implement blockchain applications could attain critical competitive advantages.