Firefighters are investigating an Automatic Fire Alarm (AFA) at the Metropolitan Apartments on London Circuit.
Following the AFA, a resident called Emergency Triple Zero (000) to report a smell of smoke.
ACT Fire & Rescue has four pumpers, the Bronto Aerial Unit and a commander on scene.
Fifty people have been evacuated as a precaution.
Crews are searching each floor for sign of fire.
Update to come.