Abstarct: In this study, the Asmari Formation (Oligo-Miocene), the most important reservoir of oil fields in southern Iran, which contains cryogenic carbonate sequences is assessed. According to petrographic studies, the main faces of this formation were found to be tidal, coastal, lagoon, barrier and open marine. Due to the gradual transformation of the facies into each other, the absence of continuous rifts and the absence of slope and slide facies, it was concluded that the Asmari Formation facies were deposited on a shallow ramp-type carbonate platform in the studied field. Sequence stratigraphy studies were performed using data from petrography, well logging and in particular, gamma log. In this study, the sequences were detected by investigating the sequence of faces and their stacking pattern and the standard deviation of gamma log. According to faces sequences and Sequence stratigraphy investigations, the Asmari reservoir of the studied field consists of 6 third order sequences, where 7 sequence boundary are of the type one (erosional) and type 2 (non-erosional) and 6 maximum flooding Surface are determined in these sequences. The system tract formed in these sequences includes a transgressive system tracts and highstand system tracts. After detecting the sequences, the quality of the reservoir in each system tract was determined baxsed on petrophysical parameters. By examining the results, it was determined that in a late transgressive system tract and early highstand system tract which are extended from the Grainstone facies, bioclast and the coastal facies, the reservoir has a higher quality. However, the quality of the reservoir has decreased with the appearance of tidal and anhydrite facies in the early transgressive system tract and Late highstand system tract. The fifth sequence was recognized as the best reservoir zone due to its excellent reservoir quality in the later Transgressive system tract and its early highstand system tract.