Abstract <p>At the end of January 2024, there was a strong cyclone in the northern Sea of Japan, which paralyzed the life of the region for several days. The features of extreme sea level oscillations in the Sea of Japan formed under the influence of this cyclone were studied on the basis of analyzing coastal tide gauge records. Using digital filters and frequency-time analysis, sea level oscillations of different frequency scales were identified, and their maximum heights were determined. The storm surge in the Sea of Japan had small heights up to 33 cm, while high-frequency sea level oscillations reached extreme values: up to 74 cm at Rudnaya Pristan. The total height of non-periodic sea level variations at Rudnaya Pristan on January 22 was 100 cm, and the range of the oscillations reached 147 cm. Infragravity waves had a significant effect on the formation of extreme oscillations at Rudnaya Pristan. The most intense high-frequency sea level oscillations at Rudnaya Pristan occurred during the tidal high water, which increased the total sea level rise. The question of the influence of wind waves and swell on the formation of high-frequency components of the sea level oscillations at Rudnaya Pristan remains open.</p>