Аннотация:During marine research expedition provided in the frame of the Japanese-Korean–Russian Project, Sakhalin Slope Gas Hydrates (SSGH), a large (of about 4 km3) submarine landslide located in the central part of the eastern slope of Sakhalin Island was found and mapped. The age of the landslide is estimated to be less than 300 years. Underwater slope failures of such magnitude could certainly induce a strong tsunami. Based on the sediment mass distribution, we estimated the initial position of the slide body of intricate shape with approximate dimension of 6*7 km and mean thickness ~80 m. A modified and corrected version of the viscous slide model of Jiang and LeBlond (1994) was used to numerically simulate the slide-generated tsunami and to estimate the maximum tsunami wave amplitudes along the coast of Sakhalin Island. It was shown that such landslide and associated tsunami is a real threat for coastal infrastructure and gas/oil pipelines located in this region.