Lunnan region is a large-scale paleohigh with many coexisting oil and gas bearing series. At present, about 2 billions tons of proved, probable and possible oil and gas reverses have been proved there. Eight oil and gas bearing series have been found in the Ordovician, Carboniferous, Triassic and Jurassic of Lunnan region, they all bear the characteristics of large-scale multilayer oil-gas province. Ordovician is the main reservoir series where over 0.8 billion tons of oil geologic reserves were discovered, and a super large-scale marine carbonate oil and gas field has formed. Reservoir space of the carbonate reservoirs is mainly composed of dissolved hole, dissolved pore and fracture in Lunnan paleo-burial hill. Generally, dissolved holes are widely distributed among them. Reservoir developments are mainly controlled by karstification and tectonic disruption. Due to the similar geochemical characters, the Ordovician, Carboniferous, Triassic and Jurassic oil and gas reservoirs present the same oil source rock of Mid-Upper Ordovician, the latter except Ordovician are mostly of secondary oil and gas reservoirs migrated vertically by faults during the process of multiple phase tectonic movement, adjustment and reconstruction. Lunnan composite oil and gas accumulation region is situated in the vicinity of large-scale hydrocarbon generation depressions in three directions, ample oil and gas from hydrocarbon generation depressions supplied the adjacent oil and gas reservoirs once. Hereby, the succeed paleohigh is the long-term hydrocarbon accumulation region, which is favor for the formations of high quality reservors, fault systems and huge-scale composite oil and gas accumulation.