Abstract: According to core,oil testing,physical property data of exploration area in Fuxian,the relationship between reser-voir lithology,physical properties,oil resistance and electrical characteristics and between the four identified Yanchang reservoir properties limit have been analyzed.The results showed that Yanchang formation is of low-porosity,low and ultra-low permeability reservoirs and the reservoirs with best properties are Chang-3 reservoirs,with oilbearing type rarely reached oil level.