The Sirt Basin of Libya hosts significant hydrocarbon reservoirs in Paleocene shallow-marine carbonates (Upper Sabil Formation) with abundant larger benthic foraminifera. Benthic foraminifera proved to be an essential biostratigraphic tool for precise biostratigraphic dating of these carbonate platform/ramp deposits. A detailed systematic description of the Middle to Late Paleocene larger benthic foraminifera from the Sirt Basin is presented, which refines the biostratigraphic age of the Paleogene shallow-marine carbonates. Eight taxa are identified at a species level. Among them, Ranikothalia solimani is the most important taxon for the correlation of the Upper Sabil Formation. The taxa Miscellanea yvettae, Miscellanites primitivus, and Glomalveolina primaeva with co-occurrence of orthophragminid foraminifera constrain the age of the Upper Sabil Formation as Middle to Late Paleocene (Selandian-Early Thanetian).