Abstract: Northeastern Sichuan basin has now become the reef?flat large gas province with a trillion cubic meters of reserves. For its discovery, there were many reasons, of which Emei taphrogenesis viewpoint that proposed by the author over 30 years ago should play an instructive part in it. This paper presents the research process and exploration results by stages, and discusses the Emei taphrogenesis as tectonic background of reef?flat deposits in northeastern Sichuan and the controlling effect on hydrocarbon accumulation conditions of this large gas province. It is finally suggested that pay more attention to Emei taphrogenesis and study Sichuan and Tarim cratonic basins which contain both sedimentary rocks and volcanic rocks, more organic and inorganic natural gas resources will be found in the future