Abstract: This paper first expounds the Polycycle Theory of Mr.Huang Jiqing related to oil and gas in the Sichuan Basin,then enumerates the development and characteristics of 6 great cycles.It confirms that,the principal contradiction of oil and gas in Sichuan is seriously tight reservoirs,and the research on fractures and looking for porous reservoirs are two paths we must follow.Due to the reservoirs deep buried and supertight,natural gas is dominant in the Sichuan Basin,with the characteristics of early accumulation and late trap.This paper simply discusses the problem of oil resource.With advanced technique will the petroleum potential of Sichuan Basin be fully released.