Abstract: Arab-Hith play is one of the most important plays in Persian Gulf basin, in which the Jurassic Arab carbonate reservoir and Hith anhydrite constitute its basic reservoir?cap rock combination. Most of the hydrocarbons in it are provided by the source rocks of Jurassic Tuwaiq Mountain formation, Hanifa formation and Diyab formation. These source rocks with high TOC and very good oil generation potentials have entered into oil windows during the Middle?Late Eocene in large scale, while many traps had already been formed at Episode I of Alpine orogeny. So the generated oil and gas could be charged or migrated directly into the traps. Arab reservoir is characterized by wide distribution,grain limestone and seldom destruction of primary porosity during the early diagenesis, followed by widespread dolomitization and leaching during the late diagenesis, witch allowed it to have superior petrophysical property. Hith formation is characterized by thick anhydrite, broad distribution and weak damage by faulting, which allowed the hydrocarbons hardly to be migrated through it toward the upper reservoirs. The petroleum loss may only occur in phase change/pinch?out belt or near large?scale faults. Most of the hydrocarbons generated from Jurassic source rocks in this play were proximal accumulation and the lateral migrations were short in distance, so the most potential areas should range around the Jurassic intraplatform basins, while Arab reservoir’s hydrocarbon abundance depend on the sealing ability of Hith cap rock