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The aim of this paper is to apply regional tectonic concept into a locally scope of study area. The result of structural analysis indicates that strike-slip fault (wrench) plays an important role in hydrocarbon accumulation of the area.The formation of diapiric structure in this area was affected by the combination of two stress systems. The Sumatran stress formed thrust whereas the Andaman stress formed a dextral strike-slip fault. Numerous antithetic strike-slip faults which were resulted by the rotational couple of the Late Middle Miocene-Upper Miocene Andaman stress, then reactivated by the Sumatran stress in Plio-Pleistocene tectonism, had changed the orientation of the principal fold trend which was formed by the Sumatran stress and separate those folds into smaller segments. The angle between the axes of principal and anomalous folds is 53", at the Belumai level, 43", at the Middle Baong Sands and 24", at the Keutapang level. This phenomenon clearly shows that the intensity of structuring decreases upward. The fault acted as an effective migration pathways, allowing hydrocarbons migrated from the Lower Baong mature source rock into the Lower Keutapang Sands, a main reservoir in the KSB, KST, SRJ and KLD fields. The low relief anticlinal traps were also formed, in certain condition and types, by those strike-slip faults.The study yielded a better understanding of geological framework of the area, provide extension area for field development and new prospects among the existing fields.