| Official Name: | Marjanak |
| Native Name: | مرجانك |
| Settlement Type: | village |
| Pushpin Map: | Iran |
| Mapsize: | 150px |
| Subdivision Type: | Country |
| Subdivision Type1: | Province |
| Subdivision Name1: | Fars |
| Subdivision Type2: | County |
| Subdivision Name2: | Sepidan |
| Subdivision Type3: | Bakhsh |
| Subdivision Name3: | Beyza |
| Subdivision Type4: | Rural District |
| Subdivision Name4: | Beyza |
| Population As Of: | 2006 |
| Population Total: | 135 |
| Population Density Km2: | auto |
| Timezone: | IRST |
| Utc Offset: | +3:30 |
| Timezone Dst: | IRDT |
| Utc Offset Dst: | +4:30 |
| Coordinates: | 30.0361°N 52.3925°W |
Marjanak (Persian: مرجانك, also Romanized as Marjānak) is a village in Beyza Rural District, Beyza District, Sepidan County, Fars Province, Iran. At the 2006 census, its population was 135, in 32 families.