Japanese islands are washed by the Sea of ​​Okhotsk in the north, the East China Sea in the south, and from the west to the east the waters of the Sea of ​​Japan and the Pacific are splashing on its shores. The Japanese Sea is washed by the shores of Japan, Russia, the DPRK, the Republic of Korea and is connected with other seas and the Pacific by four straits: Korean (Tsushima), Laperuza (Soya), Nevelskoye (Mamia), Sangara (Tsugaru). From the south, the warm current of Kuroshio enters the Sea of ​​Japan. In winter, the northern part of the sea freezes.

In Japan, traditionally relying on the mercy of the sea, there is even a national holiday Sea Day (Umi-no Hi) on July 20, which is the official weekend.