Purpose. The purpose of this study is to investigate the parameters of the Kamchatka tsunami induced by the earthquake of July 29 (30), 2025, off the Kamchatka Peninsula, and its manifestations on the northern coast of Shumshu Island (Northern Kuril Islands), based on field survey results and numerical simulations.

Methods and Results. The results of field surveys of tsunami deposits in the northern part of Shumshu Island made it possible to determine the boundaries of maximum penetration of tsunami waves into the island interior and to measure the run-up heights at eight points. The coordinates of the maximum inundation line were recorded by GPS, and the run-up heights were determined using the Gebco_2019 Grid topographic maps. Wave generation, propagation, and run-up were numerically simulated within the framework of shallow water theory using the NAMI DANCE software package and nested grids with a minimum grid size of 8 m in the coastal zone. It was established that on the northern (Sea of Okhotsk) coast of Shumshu Island, the average run-up heights were 3–4 m and the maximum reached 6 m, whereas on the eastern (Pacific Ocean) coast of the island, they were 6–8 m, and the maximum in the Cape Pochtarev area reached 12 m (with wave penetration inland up to 110 m). It was shown that significant tsunami-induced fluctuations in sea level occurred not only off the Pacific coast of Shumshu Island on the side of the tsunami source, but also in the narrow shallow straits (First and Second Kuril Straits) separating the island from the Kamchatka Peninsula and Paramushir Island.

Conclusions. The results of numerical simulations are in good agreement with the field survey data, which confirms the reliability of the performed simulations and the possibility of applying the approach used to assess the tsunami hazard in the region. The resulting run-up heights (up to 12 m) indicate the extreme nature of the tsunami.