Around 10.10am two men entered the Ashmore Road bank and made enquiries with staff before leaving the premises.
The pair then returned a short time later armed with knives.
A female teller was physically assaulted and threatened with a knife before the men fled with a sum of cash.
No one was physically injured during the incident.
Both men are described as Pacific Islander in appearance with proportionate builds and approximately 173cm tall.
One man was wearing a green baseball cap and black sunglasses while the other man was wearing a brown hooded jumper, blue tracksuit pants with an orange stripe and black sunglasses.
Anyone with information which could assist police with their investigations should contact Crime Stoppers anonymously via 1800 333 000 or crimestoppers.com.au 24hrs a day.
Crime Stoppers is a charitable community volunteer organisation working in partnership with the Queensland Police Service.