Oil and gas resources are rich in Zagros Foreland Basin. The research on giant oil and gas ifelds in Zagros Foreland Basin will enrich petroleum geology theory of foreland basins, and can also provide reference basis for oil and gas exploration in foreland basins. Based on the data of discovered 60 giant oil and gas ifelds in Zagros Foreland Basin, this paper applies the concept and analytical method of petroleum system, dissects giant oil and gas ifelds one by one, and probes into the formation and distribution of giant oil and gas ifelds in the basin. The study shows that the source rocks of giant oil and gas ifelds are Lower Silurian Gahkum Formation, Lower Cretaceous Garau Formation, Middle Cretaceous Kazhdumi Formation, Palaeocene and Eocene Pabdeh Formation. The reservoir rocks of giant oil and gas ifelds are limestone of Oligocene and Lower Miocene Asmari Formation, limestone of Middle Cretaceous Albian and Turonian Bangestan Group, limestone of Triassic Dashtak Formation and Kangan Formation, and limestone of Permian Dalan Formation. Giant oil and gas ifelds are controlled by Miocene Gachasaran Formation evaporite rock seal and Upper Cretaceous Gurpi Formation mudstone. They accumulate in folded anticlinal trap. Giant oil and gas ifelds are mainly distributed in Iran, Iraq and Syria. Big discoveries were made from 1960 to 1979. Oil and gas are rich in the layer of Mesozoic and Cenozoic. The lithology of reservoir is mainly carbonate rock which is buried at a depth less than 3km, and the reserves are less than 1×1010bbl. The factors controlling the distribution of giant oil and gas ifelds are the formation and evolution history of basin and the evolution history before basining, the organic type of source rock, the thermal evolution and distribution, the favorable reservoiring conditions, the high-quality region and direct cap rock, and the folded anticlinal traps favorable for hydrocarbon accumulation and the fracturing pathway favorable for vertical hydrocarbon migration that formed in the process of Neocene orogenic activity and folding. These factors control the distribution area and the accumulation layer of oil and gas.%扎格罗斯前陆盆地油气资源极为丰富，开展该盆地大油气田的研究将丰富前陆盆地石油地质学理论，也可为前陆盆地的油气勘探提供参考依据。以扎格罗斯前陆盆地已发现的60个大油气田数据为基础，应用含油气系统的概念和分析方法，对大油气田逐个进行解剖，探讨了扎格罗斯前陆盆地大油气田的形成条件与分别规律。研究表明，扎格罗斯前陆盆地大油气田的油气源主要为下志留统Gahkum组、下白垩统Garau组和中白垩统Kazhdumi组及古新统-始新统Pabdeh组，主要储集于渐新统-下中新统Asmari组石灰岩、中白垩统阿尔布阶-土伦阶Bangestan群石灰岩、三叠系Dashtak组和Kangan组石灰岩及二叠系Dalan组石灰岩中，受中新统Gachsaran组蒸发岩系及上白垩统Gurpi组泥岩等封盖，在褶皱背斜圈闭中聚集成藏。大油气田主要集中在伊朗、伊拉克和叙利亚三国，在1960-1979年间有较大发现，主要富集于中生界和新生界，以碳酸盐岩储层为主，多数埋深小于3km，储量小于1×1010bbl。影响大油气田分布的控制因素包括：盆地的形成和演化及其成盆前的演化历史，烃源岩的有机质类型、热演化和展布，储层有利的储集条件，优质的区域和直接盖层，以及新近纪的造山运动和褶皱作用形成的有利油气聚集的褶皱背斜圈闭和有利油气垂向运移的裂缝通道。这些因素控制了油气的分布区域和聚集层位。
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