ACT Fire and Rescue officers attended the Alexander Maconochie Centre about 8pm on Monday, after a fire was started in a prisoner's cell.
An emergency services spokesman described the fire as "small", and said it was extinguished by the jail's corrective services personnel before fire crew arrived.
Fire and rescue conducted atmospheric monitoring to ensure the facility was safe, before handing the matter back to corrective services to deal with.
No one was injured in the incident. Police were not called to the jail.
It was unclear whether the fire was started by a prisoner, and under what circumstances.