| En Name: | Ust-Maysky District |
| Ru Name: | Усть-Майский улус |
| Loc Name1: | Уус-Маайа улууhа |
| Loc Lang1: | Sakha |
| Image View: | Ynykchan1990.jpg |
| Coordinates: | 60.4167°N 166°W |
| Image Coa: | Coat of Arms of Ust-Maisky rayon (Yakutia).png |
| Federal Subject: | Sakha Republic |
| Adm Data As Of: | June 2009 |
| Adm Ctr Type: | settlement |
| Adm Ctr Name: | Ust-Maya |
| Urban-Type Settlement Of District Significance Type: | Settlements |
| No Of Urban-Type Settlements Of District Significance: | 6 |
| Selsoviet Type1: | Rural okrugs |
| No Of Selsoviets Type1: | 5 |
| No Of Urban-Type Settlements: | 6 |
| No Of Rural Localities: | 10 |
| Mun Data As Of: | December 2008 |
| Mun Formation1: | Ust-Maysky Municipal District |
| Mun Formation1 No Of Urban Settlements: | 5 |
| Mun Formation1 No Of Rural Settlements: | 5 |
| Mun Formation1 Counts Ref: | [1] |
| Area As Of: | June 2009 |
| Area Km2: | 95300 |
| Pop 2010Census: | 8629 |
| Urban Pop 2010Census: | 72.4% |
| Rural Pop 2010Census: | 27.6% |
| Established Date: | May 20, 1931 |
| Website: | http://www.ustmaya-msu.ru/ |
| Date: | July 2013 |
Ust-Maysky District (Russian: link=no|Усть-Ма́йский улу́с; Yakut: Уус-Маайа улууһа, Uus-Maaya uluuha, pronounced as /uːs-maːja uluːha/) is an administrative[2] and municipal[3] district (raion, or ulus), one of the thirty-four in the Sakha Republic, Russia. It is located in the east of the republic and borders with Oymyakonsky District in the northeast, Okhotsky District and Ayano-Maysky District of Khabarovsk Krai in the east and south, Aldansky District in the southwest, Amginsky District in the west, Churapchinsky and Tattinsky Districts in the northwest, and with Tomponsky District in the north. The area of the district is 95300km2.[4] Its administrative center is the urban locality (a settlement) of Ust-Maya. Population: 11,568 (2002 Census); The population of Ust-Maya accounts for 33.9% of the district's total population.
The main rivers in the district are the Aldan and its tributaries the Maya and Allakh-Yun.
Average January temperature ranges from -40C-42C and average July temperature ranges from in the mountains to in the river valleys.[5] Annual precipitation ranges from 250mm500mm.
The district was established on May 20, 1931. The administrative centre of the district was Solnechny from 1972–1992, after which it moved to Ust-Maya.
As of the 2021 Census, the ethnic composition was as follows:[6]
54.0%
28.4%
9.9%
1.9%
1.1%
The economy of the district is mostly based on mining, timber industry, and production of construction materials. There are deposits of gold, lead, zinc, rare metals, and construction materials.
| Urban settlements | Population | Male | Female | Inhabited localities in jurisdiction |
|---|---|---|---|---|
| Zvyozdochka (Russian: Звездочка) | 408 | 279 (68.4%) | 129 (31.6%) | |
| Solnechny (Russian: Солнечный) | 1,034 | 534 (51.6%) | 500 (48.4%) |
|
| Ust-Maya (Russian: Усть-Мая) | 2,952 | 1,429 (48.4%) | 1,523 (51.6%) |
|
| Eldikan (Russian: Эльдикан) | 1,515 | 726 (47.9%) | 789 (52.1%) | |
| Yugoryonok (Russian: Югоренок) | 272 | 176 (64.7%) | 96 (35.3%) |
|
| Rural settlements | Population | Male | Female | Rural localities in jurisdiction* |
| Kyupsky National Nasleg (Russian: Кюпский национальный) | 536 | 263 (49.1%) | 273 (50.9%) | |
| Petropavlovsky National Nasleg (Russian: Петропавловский национальный) | 985 | 478 (48.5%) | 507 (51.5%) |
|
| Ezhansky National Nasleg (Russian: Эжанский национальный) | 360 | 179 (49.7%) | 181 (50.3%) |
|
| Villages | Population | Male | Female | Rural localities in jurisdiction* |
| Belkachi (Russian: Белькачи) | 179 | 96 (53.6%) | 83 (46.4%) |
|
| Ust-Mil (Russian: Усть-Миль) | 292 | 147 (50.3%) | 145 (49.7%) |
|
| Inhabited localities in the inter-settlement territory | Population | Male | Female | Inhabited localities in jurisdiction |
| Allakh-Yun (Russian: Аллах-Юнь) | 96 | 55 (57.3%) | 41 (42.7%) |
|