Emergency services were called to the Uni Pub in Civic after reports of smoke in the building on Tuesday afternoon.
Smoke was coming from an exhaust duct on the second and third levels of the pub on London Circuit and University Ave, firefighters said at 1.20pm on Tuesday.
ACT Fire and Rescue used a thermal image camera inside the exhaust duct from the kitchen area.
The Emergency Services Agency said they determined the smoke had come from "overheating a cooking product".
By 1.40pm, fire crews - including three fire pumpers, the Breathing Apparatus Van, the Bronto Skylift Hydraulic Platform and one Commander - were preparing to depart the scene.