| Official Name: | Tasak |
| Native Name: | طاسك |
| Settlement Type: | village |
| Pushpin Map: | Iran |
| Mapsize: | 150px |
| Subdivision Type: | Country |
| Subdivision Type1: | Province |
| Subdivision Name1: | Fars |
| Subdivision Type2: | County |
| Subdivision Name2: | Rostam |
| Subdivision Type3: | Bakhsh |
| Subdivision Name3: | Sorna |
| Subdivision Type4: | Rural District |
| Subdivision Name4: | Poshtkuh-e Rostam |
| Population As Of: | 2006 |
| Population Total: | 112 |
| Population Density Km2: | auto |
| Timezone: | IRST |
| Utc Offset: | +3:30 |
| Timezone Dst: | IRDT |
| Utc Offset Dst: | +4:30 |
| Coordinates: | 30.5122°N 51.3086°W |
Tasak (Persian: طاسك, also Romanized as Ţāsak and Tāsak; also known as Kāsak) is a village in Poshtkuh-e Rostam Rural District, Sorna District, Rostam County, Fars Province, Iran. At the 2006 census, its population was 112, in 21 families.