Abstract: Based on analysis of tectonic evolution, accumulation elements, source rock, hydrocarbon source correlation and accumulation timing, by using software "Trinity" of migration and accumulation modeling, main controlling factors of oil/gas forming in JZ25-1 oilfield were analyzed, model of hydrocarbon's migration and accumulation has been established, and favorable exploration direction was pointed out. According to this model, JZ25-1 structure is a favorable structure where hydrocarbon generated from source rock of E2s3 in Liaoxi sag accumulated. And the key factor of formation of JZ25-1 oilfield is predominant space-time configuration of reservoir elements. During late Dongying period, oil generated from source rock of E2s3 and migrated through associated fault system of intensive tectonic movement, widespread sand body, large unconformity surface between E3s2 and E2s3, palaeotectonic ridge to traps of E3s2 in JZ25-1 oilfield. Sand body of E2s3 can be charged with hydrocarbon generated by close source rock of E2s3. In this area, western slope of Liaoxi sag, uplift in Liaoxi sag and paleo-ridge of structure are beneficial area of exploration.