The bodies were found at the scene of the house fire in an initial examination after the fire was extinguished on Sunday afternoon by Queensland Fire and Emergency Services, a statement issued by the Queensland Police.
The missing residents include a 34-year-old man and five boys, Xinhua news agency reported quoting police.
A port-mortem and scientific examination will take place to confirm the identities of the deceased.
The police added that a 28-year-old woman and a 21-year-old woman were able to escape the property and were rushed to hospital, where they are in stable condition.
The fire destroyed the home and spread to three neighboring properties, which sustained damage.
Investigations are continuing to determine the cause of the fire, according to the police.