| Official Name: | Koljaku |
| Settlement Type: | Village |
| Subdivision Type: | Country |
| Subdivision Name: |  Estonia |
| Subdivision Type1: | County |
| Subdivision Name1: | Lääne-Viru County |
| Subdivision Type2: | Parish |
| Subdivision Name2: | Haljala Parish |
| Population As Of: | 2006 |
| Population Total: | 46 |
| Timezone: | EET |
| Utc Offset: | +2 |
| Timezone Dst: | EEST |
| Utc Offset Dst: | +3 |
Koljaku is a village in Haljala Parish, Lääne-Viru County, in northeastern Estonia.[1]