The data on the geological records of the paleotsunamis on the coast of one of the inhabited bays of Shikotan Island have been represented. The studied area is located on the side of the South Kuril Strait, which is currently being actively developed. The purpose of the article is to establish the chronology of the strongest tsunamis that occurred here in the middle-late Holocene, to evaluate their parameters and recurrence. Data on the sections of Holocene deposits, selected on lowland within head of the bay was also attracted. The diatom analysis was used as well as lithological study for identification of paleotsunami deposits. Tsunami sands include marine and brackish-water diatom species, benthic sublittoral forms predominate, the plankton sublittoral species has been found also. Finally, the oceanic diatoms, which came from deep-sea straits, have been represented in small numbers. The grain size composition of tsunami sands is very different depending on the sedimentation conditions existing on the coas