The reserves of hydrocarbons trapped in gas hydrate deposits are estimated to be enormous, especially comparing with the proven geological resources of natural gas. At the same time the origin of gas hydrate deposits is still debatable. Comparison of the component composition of hydrocarbon mixtures obtained as a result of abiogenic synthesis in the laboratory under thermobaric parameters similar to the conditions of the Earth’s mantle with the composition of samples of natural gas hydrates shows their similarity. This confirms our suggestion about the possible contribution of deep hydrocarbons in gas hydrate formation. Gas hydrate deposits could be formed as a result of upward vertical migration of deep hydrocarbon fluids along faults and fractures.