| Official Name: | Tagarkhay |
| Native Name: | Тагархай |
| Settlement Type: | Selo |
| Pushpin Map: | Russia Buryatia#Russia |
| Subdivision Type: | Country |
| Subdivision Name: | Russia |
| Subdivision Name1: | Republic of Buryatia |
| Subdivision Name3: | Tunkinsky District |
| Subdivision Type4: | Municipality |
| Utc Offset1: | +8:00 |
| Coordinates: | 51.8667°N 125°W[1] |
Tagarkhay (Russian: Тагархай; Buriat: Таһархай, Taharkhai) is a rural locality (a selo) in Tunkinsky District, Republic of Buryatia, Russia. The population was 382 as of 2010.[2] There are 5 streets.
Tagarkhay is located 61 km northeast of Kyren (the district's administrative centre) by road. Arshan is the nearest rural locality.[3]