Abstarct: Sedimentary basin analysis is a useful method for determining the evolution and hydrocarbon generation of the source rocks. In this study, geochemical modeling and hydrocarbon generation potential evaluation of the Pabdeh Formation in one of the oil fields, southwestern Iran. For this purpose, 47 samples from different oil fields in the studied area were analyzed by Rock-Eval 6 pyrolysis system. The kerogens are mostly type II, III and II/III, however the samples are mainly immature and are within diagenesis stage. The 90% of samples have fair to excellent hydrocarbon generation potential. The organic facies of the formation are in the rage of B, BC, C and CD. The organic facies variations are due to lateral facies changes and sea-level fluctuations during deposition of this fomation. The Pabdeh Formation can be divided into 3 geochemical zones. The upper and lower zones were deposited during sea level regression with low quantity of TOC and HI as well as kerogen type III. However, the middle zone that deposited during the sea level transgression has high quantity of TOC and HI with kerogen type II.The Pabdeh Formation in the studied area can be characterized as high hydrocarbon generation potential but immature source rock and the middle zone of this formation may represent an unconventional hydrocarbon reserve. Using burial and thermal history modeling of three wells (A1, A2 and A3) in southern Dezful embayment, the effects of sedimentation, subsidence and uplift of the sedimentary basin on the temperature changes associated with depth and time and thus maturity of the Pabdeh Formation has been studied. The burial history diagrams show that the sedimentary basin had low subsidence rate during the sedimentation of Pabdeh Formation in Paleocene to Oligocene. The highest rate of subsidence happened during the middle to late Miocene, associated with deposition of the Gachsaran Formation. The Pabdeh Formation was in deepest burial depth from 2074m to 3220m, in the Pliocene, and after that, from Pliocene to present day, it has been uplifted. This uplift is concomitant with the main folding phase of the Zagros orogeny. baxsed on the burial history and thermal maturity models, from middle Miocene, the Pabdeh Formation was exposed to the temperature higher than 60° C and reached to the 100° C in middle Pliocene. However due to the uplift of basin and changes of appropriate situations, it did not have enough time for complete thermal maturation and hydrocarbon generation. According to low amount of Ro (<0/6%), the Pabdeh Formation in the studied area is in the beginning of oil window and due to low amount of thermal maturity, it can be considered as a high potential but immature source rock.