Researches concerning freshwater gastropoda in Turkey have increased significantly in recent years. Among Prosobranchia, Bithyniidae are in an interesting position due to limited knowledge available about species diversity, distribution and ecology. Although most of species belong to Bithyniidae known from Balkans and Greece, only few species of Bithyniids have been known from Turkey so far, including Bithynia tentaculata, B. leachii, B. pseudemmericia, B. phialensis, B. badiella, B. pesicii, B. yildirimi and Pseudobithynia pentheri, P. yildirimi. In this study conducted on Lake Uluabat, a limnobenthos survey was carried out from 12 different sampling sites across the lake. This study aims to describe a new Bithynia from the eutrophic Lake Uluabat located in South Marmara Region of Turkey and provide data about the ecology of the new species that living in a restricted location in the lake.