During Albian time, a large but gentle depression was developed over Dezful Embayment extending to the northern part of Persian Gulf. Strong anoxic condition prevailed development of bituminous marls of Kazhdumi Formation in central part of the depression. Organic richness, quality, distribution, and maturity of Kazhdumi Formation in northeast margin of Arabian plate (Dezful Embayment, Persian Gulf, Abadan Plain and Fars Region) are evaluated in this study. Rock-Eval pyrolysis data, such as T_max, S₁, S₂, oxygen index (OI), and total organic carbon (TOC), petrographic studies, and burial history information of 64 wells in 37 oil and gas fields and five outcrops are applied to achieve focused aims. Based on the interpretations of TOC and S₂ data, Kazhdumi organic matter richness increases toward Dezful Embayment and the lowest values are recorded in central Persian Gulf (Qatar Arch). Using constructed burial and temperature histories, T_max and vitrinite reflectance (VR_r) values, the variation of maturity level are found similar to that of organic matter richness which highest and lowest maturities are observed in Dezful Embayment and Qatar Arch, respectively. Kerogen type studies were carried out based on Rock-Eval parameters and type II/III kerogen assessed for organic matter of Dezful Embayment and terrigenous or type III for those of Persian Gulf.