| Official Name: | Lash Wa Juwayn |
| Native Name: | لاش جوین |
| Native Name Lang: | pa |
| Settlement Type: | District |
| Coordinates: | 31.8261°N 61.23°W |
| Pushpin Map: | Afghanistan |
| Pushpin Label Position: | right |
| Subdivision Type: | Country |
| Subdivision Name: |  Afghanistan |
| Subdivision Type1: | Province |
| Subdivision Name1: | Farah |
Lash wa Juwayn (also transliterated Lash o Jawain) is a district in Farah Province, Afghanistan. Its population, which is approximately 30% Pashtun and 70% Tajik (ethnic Persian or Fars-tabar), was estimated at 28,000 in January 2005.[1] The main town, also called Lash wa Juwayn, is situated at 508 m elevation by Daryache-ye Sistan lake.