Abstract: The Zongshan section in Gamha of southern Tibet has long been considered as the standard section for the Cretaceous of the Tethyan Himalayas The Late Cretaceous strata are well exposed in this area and contain abundant foraminiferal fossils，from which 130 species of 52 genera have been identified. The rocks are mostly marine carbonates. Systematic studies of the microfauna and petrology have been conducted to establish a new stratigraphic framework for this area and the relationship between the foraminifera1 faunas and the sea level changes.The Late Cretaceous strata in this area can be subdivided into three Formations, which are(in ascending order)the Lengqingre Formation，Gangbacunkou Formation and Zongshan Formation. They are roughly of the Cenomanian to early Turonian，middle Turonian-Santonian and Campanian-Maastrichtian age. Ten planktonic foraminiferal zones were recognized，which can be correlated with similar zones in Pakistan， Europe and America In addition，5 foraminlferal faunas， represented by Rotalipora fauna， Whiteinella-Helvetoglobotruncana fauna ，Dicarinella-M arginotruncana fauna ，Globotruncana-Globotruncanita fauna and Orbitoides-Omphalocyclus fauna，can be recognized. The evolution of the foraminiferal faunas in this area occurred mainly in response to the eustatic changes which have affected biological niche of the microplankton.