Abstract: Jiangsu oilfiled has so complex condition under ground structure that it is considered as "the examination room of geologist". It is featured by fractural faults,severe multiple and igneous rocks,thus the technology of fine structural interpretation plays key role in progressive development of little fault block oilfield. In GJ and CB oilfield,horizons and fault in the area were accurately demarcated and interpretation,by making full use of fine technologies of interpretation and processing,offering the precision structure modle under ground. And area of oil-bearing and geology reserves continually increased.