Kholmsk (Mauka till 1905, and Maoka from 1905 to 1946) is a city in the Far East of Russia, the administrative center of Kholmsk city district in the Sakhalin Region. It stands on the southwest coast of the Sakhalin Island, on the shore of the gulf of Nevelsky Strait of the Sea of Japan, 83 km to the west of Yuzhno-Sakhalinsk. The city with the population of 28 521 people (as of 2016) takes the overall area of 32 km². It is the third largest city as regards population and the second city most important economically in the Sakhalin Region.

It is Sakhalin's largest transport center that has a non-freezing sea port with two terminals, three railway stations and a highway junction. Kholmsk is connected to Vanino with the sea rilway passenger-and-freight ferry crossing Kholmsk-Vanino. The federal highway P495 Kholmsk — Yuzhno-Sakhalinsk starts from the city.

Kholmsk is a large economic, industrial and cultural center of the Sakhalin Region, thea center of deep sea fishing and ship repair.

The city was founded on May 21, 1870 as the Russian military post of Mauk. From 1905 to 1945 it belonged to Japan under the name of Maoka. In 1945 it was returned to the USSR and renamed into Kholmsk in 1946.

The next Japanese city — Vakkanay — is located on the northernmost tip of the island of Hokkaido at the 180 km distance to the south of Kholmsk.

Kholmsk has a moderate climate, transitional from monsoonal to marine.