An accurate prediction of the sub-surface pore pressures is a necessary requirement to safely, economically and efficiently drill the well required to test and produce oil and natural gas reserves. An understanding of the pore pressure is a requirement of the drilling plan in order to choose proper casing points and design a casing program that will allow the well to be drilled most effectively and maintain well control during drilling and completion operations. The purpose of this study is to develop a pore pressure prediction strategy for an oil field in Iran. the basic concepts used in pore-pressure prediction are defined, and the way in which pore pressure can be estimated using velocity measurements is explained. A predrill estimate of pore pressure can be obtained from seismic velocities using a velocity to pore pressure transform calibrated with offset well data..another way to estimate of pore pressure is use directly from acoustic impedance