Aitamir Formation (Albian-cenomanian) is exposed south of Agh-Darband area in eastern Kopet-Dagh basin. This formation in the study area is composed of sandstone, shale, siltstone and carbonate lithofacies. Green grains of glaucony are present with different amounts within lithofacies. Based on lithofacies variations as well as characteristics of glaucony grains, it is interpreted that the Aitamir Formation was deposited in a shallow open marine environment. The major evidences for diagenetic features in sandstones are compaction, cementation, alteration, dissolution and replacement. Glauconitization is a one of the most important diagenetic process that has been taken place in this formation. This process is operated as replacement for feldspar, rockfragment, quartz, fossil fragments, mud and calcite cement. Diagenetic process affected the carbonate rocks in the form of micritization, compaction, cementatin (with fibrous, poikilotopic, syntaxial, granular and blocky fabrics), dissolution and neomorphism. Lastly, paragenetic sequence of the Aitamir Formation can be divided into three different stages including: early (eogenesis), late (mesogenesis) and uplift (telogenesis). This information can help in better understanding of the reservoirs characteristics of this and similar rocks within the Kopet-Dagh Basin.