The current work is based on quantitative and qualitative analyzes of the calcareous foraminifera of the latest Paleocene-earliest Eocene sequence at Gebel Duwi, Quseir region, Red Sea, Egypt. Two rock units are studied in the Late Paleocene–Early Eocene sequence: Esna Formation at the base and Thebes Formation at the top. Four planktic foraminiferal biostratigraphy are identified; late Paleocene P5 zone and early Eocene E1–E3 zones. The foraminiferal parameters such as total foraminiferal number (TFN), benthic foraminiferal number (BFN), planktic foraminiferal number (PFN), Planktic/Benthic ratio (P/B%), Epifaunal/ Infaunal ratio (E/I%), Calcareous/ Arenaceous ratio (C/A%), abundance, diversity, and Benthic Foraminiferal Oxygen Index (BFOI) in additional to fieldwork and the microfacies investigation were incorporated to divide the studied sequence into three third order sequences of depositional bounded with four sequence boundaries. The morphological characteristics and assemblages of benthic foraminiferal are heavily influenced by variations in oxygen concentrations at the sediment water interface; these variations are reflected at the wall thickness and size of recorded taxa. These taxonomic variations and morphologic were quantified as a dissolved oxygen indicator. Three types of benthic foraminifera were classified into dysoxic, suboxic, and oxic indicators. These indices are then used for paleoenvironmental interpretations. The environments ranged from inner neritic to upper bathyal (∼150–300 m deep) during the deposition of the latest Paleocene–earliest Eocene succession.