Abstract Historical tsunami events have impacted the Istanbul coasts along the Sea of Marmara. Offshore seismic sources may trigger these tsunamis directly or through coseismic underwater failure. The 1999 izmit Bay tsunami led to more comprehensive analyses of these events which are generally caused by underwater failures close to the target coastline. Waves so generated can arrive at nearby coastlines in minutes, causing extensive damage and loss of life. Here this paper propose, on the basis of tsunami models in the Sea of Marmara and methodology used internationally, first generation tsunami inundation maps for the areas along the southern coast of IstanbuL Such maps for selected areas help to understand the possible effects on those regions and should only be used for evacuation plaiming and reducing possible hazard.