Manifestations of gas volcanism in the Black Sea reveal a direct connection with the location of presumed accumulations of gas hydrates or with their actual findings during sampling of the upper layer of bottom sediments with impact gravity tubes. The thermobaric conditions for stable gas hydrate accumulations in the Black Sea, as well as the mechanisms of their formation, are considered. In the Black Sea, two types of gas hydrate accumulations have been identified: (a) areal, confined to the continental slope, fault zones, river fans, and associated with the discharge of formation fluids in places where sedimentary strata are exposed by erosion; and (b) ring deposits within mud volcanoes, where gas and gas-containing fluids can migrate upwards toward the sea bottom and favorable pressure–temperature conditions exist for the formation of methane hydrates. In both the first and second cases, we can confidently assert that there is a close spatial connection between the occurrence of gas hydrates in the Black Sea and the location of gas seeps, torches, and fountains, as well as with anomalous gas emissions and fire phenomena as a result of earthquakes. Geological and geophysical observations suggest that hydrate saturated sediments near underwater mud volcanoes in the deep part of the Black Sea may represent potential deposits of gas hydrates.