The ammonite biostratigraphy of the Upper Barremian- Lower Albian sequences (Sarcheshmeh and Sanganeh formations) in the Koppeh Dagh basin are studied. Based on assemblage faunas 12 biozones are suggested for the Upper Barremian to Lower Albian sequences. The Heteroceras spp. and Martelites securiformis zones are suggested for the Upper Barremian Sub-Stage. The Deshayesites oglanlensis, Deshayesites weissi, Deshayesites deshayesi and Dufrenoyia sp. zones are proposed for the Lower Aptian Sub-Stage. The Parahoplites spp. and Epicheloniceras subnodosocostatum zones are suggested for the Middle Aptian and the Acanthohoplites spp. and Hypacanthoplites uhligi zones for the Upper Aptian Sub-Stage. The Lower Albian biozones are Leymeriella tardefurcata and Douvilleiceras sp.