Property of rock are very important in oil and gas industries to characterize the reservoir to find the best zone that have to be perforated for oil & gas production. Especially in carbonate reservoir, which has very complex characteristic because of diagenesis and different in deposition environments. This study has been done to calculate petrophysical property in Reservoir Field "S" at Paciran Limestone Formation. The property of rock consist of volume shale (Vsh), porosity (φ), saturation water (Sw) and permeability. Vsh determined from gamma ray log then validated by XRD, φ determined from neutron and density log then validated by core porosity, Sw determined from resistivity log and be validated by Special Core Analysis (SCAL). The permeability determined by Hydraulic Flow Unit (HFU) method from core data. The result of the calculation show that the reservoir has average clay content 0 - 20%, means the porous are dominated filled by fluid, with the average value of porosity is 45%, and the lowest saturation water is 25%. Then calculation of HFU showed that there are seven type of permeability based on their capability to flow the fluid, with the value of permeability is about 0.27 - 78 mD. By analyze all of those property of rock, the best perforation zone is on depth which has permeability dominant of type 1-3 and the HFU method could be used to other wells with no data core, this help to increase the production with lower expense.