| Official Name: | Ashtajin |
| Native Name: | اشتجين |
| Settlement Type: | village |
| Pushpin Map: | Iran |
| Mapsize: | 150px |
| Subdivision Type: | Country |
| Subdivision Type1: | Province |
| Subdivision Name1: | Qazvin |
| Subdivision Type2: | County |
| Subdivision Name2: | Takestan |
| Subdivision Type3: | Bakhsh |
| Subdivision Name3: | Central |
| Subdivision Type4: | Rural District |
| Subdivision Name4: | Qaqazan-e Sharqi |
| Population As Of: | 2006 |
| Population Total: | 456 |
| Population Density Km2: | auto |
| Timezone: | IRST |
| Utc Offset: | +3:30 |
| Timezone Dst: | IRDT |
| Utc Offset Dst: | +4:30 |
| Coordinates: | 36.2333°N 49.7617°W |
Ashtajin (Persian: اشتجين, also Romanized as Āshtajīn, Ashtāchīn, Ashtagin, and Ashtajīn; also known as Ashtākīn) is a village in Qaqazan-e Sharqi Rural District, in the Central District of Takestan County, Qazvin Province, Iran. At the 2006 census, its population was 456, in 101 families.