| Kantegir | |
| Mouth: | Tes-Khem |
| Mouth Coordinates: | 50.2972°N 95.0831°W |
| Progression: | Tes-Khem→ Uvs Lake |
| Subdivision Type1: | Country |
| Subdivision Name1: | Russia |
| Length Km: | 139 |
| Basin Size Km2: | 4390 |
The Erzin (ru|Эрзин) is a river of Tuva, Russia. It is a right tributary of the Tes-Khem. It is long, and has a drainage basin of .