Driving in Australia on an Overseas Driver's Licence
Overseas drivers visiting Australia, who do not hold a permanent visa, will be regarded as 'visiting drivers' and can use their valid overseas licence to drive. Most Australian states and territories (the exception being the Northern Territory) allow visiting drivers to drive indefinitely on their overseas licence as long as it is current. It is only when there is a change in visa/citizenship status or the overseas licence expires that an overseas driver is required to take out an Australian issued driver licence. In the Northern Territory a person is required to obtain a Northern Territory issued driver's licence after three months or apply to be granting an exemption from holding a local licence if they wish to continue to drive.
It is important to remember that a person can only drive vehicles which their overseas licence authorises them to drive and they must drive according to any conditions on their overseas licence.
Please be aware that a person who is driving in Australia must carry the overseas licence with them at all times whilst driving along with either an International driving permit OR an English translation if the overseas licence is not written in English.
http://austroads.com.au/driver-licences/overseas-driver-licences.