Russkoye Ustye (Russian: Ру́сское У́стье; Yakut: Русскай Устье, romanized: Russkay ustye) is a rural locality (a selo), the only inhabited locality, and the administrative center of Russko-Ustinsky Rural Okrug of Allaikhovsky District in the Sakha Republic, Russia, located 120 kilometers (75 mi) from Chokurdakh, the administrative center of the district.

The noun ustye means "the river mouth" and the adjective Russkoye ("Russian") apparently refers to this channel's being the one located the farthest to the west (i.e., the one closest to [European] Russia).

Similarly, the easternmost channel of the delta has been known as the Kolymskoye Ustye, i.e., the river mouth closest to the Kolyma (the Indigirka's neighbor to the east).

Due to the remarkable geographic isolation of the settlement, its residents preserved much of their ancestors' beliefs, customs, and folklore into the 19th and 20th century, which made Russkoye Ustye a favorite destination for Russian ethnographers and cultural anthropologists, such as Gerhard von Maydell.

[9] According to a locally recorded legend, the villagers' ancestors originally left European Russia during Ivan the Terrible's persecution campaigns in the late 16th century, although, as Rasputin suggests, reaching the Indigirka may have taken them a long time.