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Abstract. This paper deals with the sequence stratigraphy of the Oligocene (Rupelian-Chattian)-Early Miocene (Burdigalian) Asmari Formation based on microfacies analysis of the sediments in the Ghale Nar Oilfield, central area of Zagros fold-thrust belt. Fourteen facies types typical for upward shallowing trend from open marine (MF 1-3), to shoal (MF 4-5), semi-restricted and restricted lagoon , and finally to near-shore lagoon (MF 13-14) depositional environments were identified. Based on the environmental interpretations, we reconstructed a homoclinal ramp mainly represented by its inner and middle sectors. Facies types MF 4-14 are characterized by the occurrence of large and small porcelaneous benthic foraminifera representing a shallow-water setting of an inner ramp influenced by wave-and tide-related processes. MF1 (Pabdeh Formation), and 2-3 with planktonic, large and small hyaline benthic foraminifera represent between fair weather wave base (FWWB) and storm wave base (SWB). Four third-order depositional sequences were recognized. In order to better correlate the identified sequences with those pre-defined of the Asmari Formation in the Dezful Embayment and the Izeh zone that are chronologically well-known, we use their number instead of their name. Sequence 2 mainly consists of an open marine environment in the base, followed by semi-restricted to restricted lagoonal facies. Sequences 36 are characterized by semi-restricted to restricted lagoonal facies. Moreover, the regional relative sea-level change curves correlate well with the global sea-level change curves.