| Official Name: | Tajanak-e Sofla |
| Native Name: | تجنک سفلی |
| Settlement Type: | village |
| Pushpin Map: | Iran |
| Mapsize: | 150px |
| Subdivision Type: | Country |
| Subdivision Type1: | Province |
| Subdivision Name1: | Mazandaran |
| Subdivision Type2: | County |
| Subdivision Name2: | Sari |
| Subdivision Type3: | Bakhsh |
| Subdivision Name3: | Central |
| Subdivision Type4: | Rural District |
| Subdivision Name4: | Mazkureh |
| Population As Of: | 2006 |
| Population Total: | 144 |
| Population Density Km2: | auto |
| Timezone: | IRST |
| Utc Offset: | +3:30 |
| Timezone Dst: | IRDT |
| Utc Offset Dst: | +4:30 |
| Coordinates: | 36.6167°N 53.0333°W |
Tajanak-e Sofla (Persian: تجنک سفلی, also Romanized as Tajanak-e Soflá) is a village in Mazkureh Rural District, in the Central District of Sari County, Mazandaran Province, Iran. At the 2006 census, its population was 144, in 37 families.