The molluscan assemblage of the Canakkale Strait (Turkish Strait System) was studied at depths ranging from 10 to 22 m, by means of the van Veen grab seasonally during 2006 and also at 7 stations, that are located in the middle part of the Canakkale Strait, at depths ranging from 40 to 83 m by means of box-core, van Veen grab and dredge during the summer of 2007. A total of 283 species were found in the strait. Krachia cylindrata (Jeffieys, 1885) was newly recorded in the East of the Mediterranean Sea and a total of 5 species [Cerithiopsis scalaris (Locard, 1892), Melanella monterosatoi (Monterosato, 1890), Bela fuscata (Deshayes, 1835), Mangelia melitensis Cachia and Mifsud, 2008 and Cylichnina laevisculpta (Granata-Grillo, 1877)] were newly recorded in the Turkish Seas. Furthermore, 37 mollusc species were newly recorded in the Turkish Strait System and 140 more species were recorded for the first time from the Canakkale Strait. Bittium reticulatum (da Costa, 1778) and Mytilus galloprovincialis Lamarck, 1819, were the most important species, representing 52% of the total 37024 specimens. No seasonal differences were found, while hydrodynamic conditions seem to be the factor controlling Mollusca recruitment in the Canakkale Strait.