Sarvak Formation in Ahvaz Square as one of the important reservoir formations in the southwestern region of Iran which needs to be studied in drilled wells. In the present study, after careful investigation of sources and data collection and well logging, using Geolog software and using definitive calculation method, lithology of the excavated formation, porosity distribution, water saturation and hydrocarbon content were determined, and reservoir zones located in the studied well located in Sarvak Formation were investigated. In addition, determining the type of porosity in Sarvak Formation on the basis of velocity deviation diagram was also on the agenda. For this purpose, information about the responses of common well graphs in well-studied wells such as gamma ray, caliper, resistance, density, neutron and acoustic porosity diagrams and photoelectric effect were provided along with the porosity data obtained from core analysis. After the analysis, the results show that the lithology of Sarvak Formation in the studied well is mainly of lime type and has small amounts of shale, sand, and dolomite. The lithological column of Sarvak Formation in the petrophysical model of the well shows the lithological distribution in the excavation depth. In addition, the calculations showed that the shale volume in the studied well is approximately 10%. The volume of shale in Sarvak Formation in the studied well is very low, which is in accordance to low volume of shale in Sarvak formation. Lithological and stratigraphy studies in Sarvak formation showed that a very small amount of marl and shale is present in Sarvak Lime. On the other hand, the distribution was obtained by combining two neutron and density graphs. In general, it seems that in the study formation in the well, the porosity is on average 6%. It seems that the formation is lithologically in the group of rocks with low porosity family. In addition, the analysis of the results showed that the porosity calculated from the combination of the two neutron and density graphs is in good agreement with the results of the core analysis. To further investigate the type of porosity in Sarvak Formation in the studied well, velocity deviation diagram was obtained. In general, it seems that the predominant porosity in the formation in the case well is of moldic and intra-fossil type. In this type of porosity, the permeability of the rock is low. Given that the calcareous lithology is estimated, the presence of moldic and intra-fossil porosity with low permeability is not unexpected. Finally, reservoir zoning was performed based on reservoir quality based on hydrocarbon saturation in porous space. A total of 6 zones were estimated. Zones 1, 3, and 5 have better reservoir quality than other zones, respectively. Because they have more porosity and hydrocarbon saturation. Zones 2 and 6 are very dense in terms of porosity and do not have reservoir quality. The results show that the best reservoir zone is zone number 1, which constitutes only 3.5% of the total thickness of the drilled formation and is located at the beginning of the drilled depth in the well. Zone No. 2, which does not have reservoir quality, contains 56% of the total thickness of the formation, which has reduced the reservoir quality in Sarvak Formation in the studied well.