| En Name: | Mastakh |
| Ru Name: | Мастах |
| Coordinates: | 63.7228°N 124.1894°W |
| Map Label Position: | right |
| Federal Subject: | Sakha Republic |
| Adm District Jur: | Kobyaysky District |
| Adm Selsoviet Jur: | Lyuchcheginsky 2-y Rural Okrug |
| Adm Selsoviet Type: | Rural okrug |
| Adm Ctr Of: | Lyuchcheginsky 2-y Rural Okrug |
| Inhabloc Cat: | Rural locality |
| Inhabloc Type: | Selo |
| Mun District Jur: | Kobyaysky Municipal District |
| Mun District Jur Ref: | [1] |
| Rural Settlement Jur: | Lyuchcheginsky 2-y Rural Settlement |
| Mun Admctr Of: | Lyuchcheginsky 2-y Rural Settlement |
| Pop 2010Census: | 617 |
| Postal Codes: | 678313 |
Mastakh (Russian: Мастах; Yakut: Мастаах, Mastaax) is a rural locality (a selo) and the administrative center of Lyuchcheginsky 2-y Rural Okrug of Kobyaysky District in the Sakha Republic, Russia, located 285km (177miles) from Sangar, the administrative center of the district.[2] Its population as of the 2010 Census was 617;[3] up from 577 recorded in the 2002 Census.