This study explains the stratigraphical and palaeoenvironmental significance of Bartonian - Priabonian ( Middle - Late Eocene) fossils, the fauna and flora obtained from the Bascesme formation of the Cardak - Tokca basin ( western Anatolia). The studied sequence is an outcrop from the Bascesme formation, deposited in a shallow-marine to coastal environment without stratigraphic breaks. Forty genera and 58 species have been recognized in the palynological assemblage of the Bascesme formation. A well-preserved diverse palynomorph and foraminiferal assemblages yield the Middle - Late Eocene age for the Bascesme formation. In western Anatolia, mangrove elements Nypa and Pelliciera have been first recorded in this study. The pollen of Mauritia and Acrostichum occur in the back-mangrove environment. Lowland - Riparian and montane elements are characterized by dominance of Myricaceae, Betulaceae, Engelhardia, Fagaceae, Myrtaceae, Anacardiaceae and Taxodiaceae, Pinus, Abies, Picea, Cathaya, Quercus and Castanea, respectively. Fresh-water elements are represented by Sparganiaceae, Pediastrum sp. and Aglaoreidia cyclops.