Abstract: The author of this paper describes four principal factors for the formation of nautral gas pools under a dynamic balance regime based on the relationship between the generation, accumulation and dissipation of natural gas.The source rocks and the stage of gas generation peak are the most important factors in the formation of gas pool while sealing efficiency and tectonic settings are the important factors for the gas accumulation and dissipation. Therefore, it is concluded that four fundamental factros for the formation of natural gas pools are of abundant gas source, the late stage of gas generation peak, excellent sealing efficiency and stable teetenic settings.