Abstract: Through summarizing the geological characteristics of the Nankeng molybdenum deposit in Nanjing County, Fujian Province, this study concludes that the deposit belongs to porphyry-type molybdenum ore deposit. Molybdenum orebodies occur mainly along the contact zone between early Yanshanian granite and surrounding rock Wenbingshan Formation, predominantly within early Yanshanian granite. The orebodies are controlled by gently-dipping quartz veins and stockwork quartz veinlets. There are two types of ores: quartz vein and quartz veinlets. The Mo-bearing deposit is characterized by weak magnetic anomalies, well development of primary halo and secondary halo, with the secondary halo anomaly showing good mineralization especially at depth. Alteration closely related to Mo mineralization contains greisenization and silicification and etc. The indicators for prospecting mainly are early Yanshannian granite, Bailou-Xialou fault zone,Wenbingshan Formation of late Triassic, greisenization and silicification, geophysical and geochemical anomaly, etc. The understanding above is of some references for finding similar molybdenum ore deposits in the area.