Dolinsk (Russian: Долинск; Japanese: 落合) is a town and the administrative center of Dolinsky District of Sakhalin Oblast, Russia, located in the southeast of the Sakhalin Island in the valley of the Naiba River and its tributaries, about 45 kilometers (28 mi) north of Yuzhno-Sakhalinsk and 10 kilometers (6.2 mi) from the coast of the Terpeniye Bay of the Sea of Okhotsk.

[8] The present site of the town was the location of the Ainu settlement Ziancha until 1884, when the Russian village of Galkino-Vraskoye (named after Mikhail Galkin-Vraskoy) was founded.

[citation needed] The Treaty of Portsmouth saw it transferred to Japanese control in 1905, along with the rest of southern Sakhalin.

The Red Army retook control of the whole of Sakhalin in 1945, during the closing stages of World War II.

Lying exposed to moist southeasterly flows from the Pacific Ocean, it is substantially wetter than either Yuzhno-Sakhalinsk or Alexandrovsk-Sakhalinsky, and receives very heavy snow in winter.