Abstract: By summarizing distributional characteristics of oil and gas of the northern slope belt in Biyang sag,on the basis of the oil sources, nose-like structure, sand body extension direction and size, fault system characteristic and their configuration relationships, northern slope belt can be divided three types of accumulation models:migration-accumulation of convergent type, migration and accumulation along the fault-adjusting hydrocarbon migration along the northeast of sag, controlling accumulation model and slope selfsource and self-reservoir accumulation models along the northwest of sag. This paper analyzed and summarized the regularities and characteristics of hydrocarbon enrichment that are ①inheritance deposition-tectonic slope is directing zone of hydrocarbon large-scale migration, and nose shaped uplift is hydrocarbon enrichment belt;②slope belt and the center of sag are favorable areas of shaping low-stand fan lithologic reservoirs and fault-lithologic reservoirs. And it pointed out that the main potential goals of the further exploration are old oilfield potential tapping, H3 lower section, fault-lithologic reservoirs in the slope belt, non-structural principal part lithology and fault-lithologic reservoirs, unconformity reservoirs in slope border shallow layer and so on.