Accurate reservoir characterization is an important stage in developing, managing the reservoir, and enhancement the production which depends mainly on a good description and precise interpretation of the reservoir facies. The study area is considered as a part of Qarun Petroleum Company's development leases which are located in the western side of Beni Suef Basin, the northeastern Western Desert which is considered the most important petroleum province in Egypt. Integrated sedimentological analysis of core description, petrographic and mineralogical constituents were carried out on the Upper Abu Roash “G" sandstone reservoir. The core description included 81.25 feet from the WON C-18 borehole helps to identify various sand bodies and distinguish four main facies groups: carbonate facies, mudstone facies, heterolithic facies, and sandstone facies. Petrographically, the sandstone facies samples have frequent amounts of monocrystalline quartz grains, few amounts of plagioclase, traces of polycrystalline quartz, common amounts of ferron dolomite, minor amounts of pore-filling kaolinite booklets and chlorite, amounts of well-developed syntaxial quartz overgrowths, traces of feldspar overgrowths. Also, we have secondary inter-and intraparticle pores, with moderate to good pore interconnectivity and the reservoir quality is moderate to good. Based on the facies, characterization, it is proposed that the stratigraphic intervals of the Upper Abu Roash “G" unit were deposited in subtidal-intertidal settings, where deposition of muddy-flat and intertidal sediments are locally interrupted by tidal-flat sand-channel deposits.