| En Name: | Mastakh 2-y |
| Ru Name: | Мастах 2-й |
| Coordinates: | 63.7408°N 124.2208°W |
| Map Label Position: | left |
| Federal Subject: | Sakha Republic |
| Adm District Jur: | Kobyaysky District |
| Adm Selsoviet Jur: | Luchcheginsky 2-y Rural Okrug |
| Adm Selsoviet Type: | Rural okrug |
| Inhabloc Cat: | Rural locality |
| Inhabloc Type: | Selo |
| Mun District Jur: | Kobyaysky Municipal District |
| Mun District Jur Ref: | [1] |
| Rural Settlement Jur: | Luchcheginsky 2-y Rural Settlement |
| Pop Latest: | 23 |
| Pop Latest Date: | 2002 |
Mastakh 2-y (Russian: Мастах 2-й, pronounced Mastakh Vtoroy) is a rural locality (a selo), and one of three settlements in Luchcheginsky 2-y Rural Okrug of Kobyaysky District in the Sakha Republic, Russia, in addition to Mastakh, the administrative center of the Rural Okrug and Byranattalakh. It is located 282km (175miles) from Sangar, the administrative center of the district and 3km (02miles) from Mastakh. Its population as of the 2002 Census was 23.[2]