| Official Name: | Posuj |
| Native Name: | پسوج |
| Settlement Type: | village |
| Pushpin Map: | Iran |
| Mapsize: | 150px |
| Subdivision Type: | Country |
| Subdivision Type1: | Province |
| Subdivision Name1: | South Khorasan |
| Subdivision Type2: | County |
| Subdivision Name2: | Birjand |
| Subdivision Type3: | Bakhsh |
| Subdivision Name3: | Central |
| Subdivision Type4: | Rural District |
| Subdivision Name4: | Alqurat |
| Population As Of: | 2006 |
| Population Total: | 72 |
| Population Density Km2: | auto |
| Timezone: | IRST |
| Utc Offset: | +3:30 |
| Timezone Dst: | IRDT |
| Utc Offset Dst: | +4:30 |
| Coordinates: | 33.0139°N 59.3006°W |
Posuj (Persian: پسوج, also Romanized as Posūj and Pasūj; also known as Posūch, Pasūch, Pasuk, Pūch, and Seyyedābād) is a village in Alqurat Rural District, in the Central District of Birjand County, South Khorasan Province, Iran. At the 2006 census, its population was 72, in 27 families.