Abstract: Mud volcanoes have gradually become a world research focus for geosciences in the past decades, with the progress of marine exploration technology. Mud volcanoes in the world are mainly distributed in the Mediterranean-Caspian-Himalayan active belt and the Pacific activity belt, dominated by tectonic activities. Although the distribution of mud volcanoes is limited in the world, the research of it is of significance. The eruptive materials of the mud volcano may carry great amount of information of the interior Earth. Mud volcano is also bound up with the formation, migration and accumulation of deep oil and gas in terms of structural trapping, thermodynamic mechanism and developmental horizons. Moreover, there is high content of methane in the gas erupted together with the mud. On one hand, It will bring affect to marine water and atmospheric environment, and on the other hand, it will collect the gas in the seabed sediments to form gas hydrate. There are large amount of submarine mud volcanoes existed in the South China Sea. To intensively study those mud volcanoes in the South China Sea is important not only in exploring the migration and evolution of Earth interior material, but also the exploration and development of the oil and gas hydrate in the South China Sea basins.