Abstract: With the increasing scale development of Jurassic reservoir in southwest of Ordos basin, high quality reserves of Jurassic reservoir were constantly produced, while the low resistance reservoirs were subtle reservoirs, there was little experience in development and exploration, oil or water layer identification was becoming in creasingly prominent. Yan-9 reservoir of Z block was a typical low resistance reservoir in southwest of Ordos basin. Analysis indicated that the pore structure was complex, the micropore rate was high and the water in the micropores was the main reason for the low resistance of the reservoir, the high degree of formation water mineralization also reduced the resistivity of the oil layer. Contrast analysis of the logging curve method, the sand layer roof structure comparison method, invasive factor and acoustic time difference intersection engraving method, fast chromatographic logging identification method in identifying the low resistance reservoir were carried out, and then favorable production targets were put forward.