"Are political parties mentioned or written in the Australian Constitution?"

Thanks for your question.

Political parties are not mentioned in the Australian Constitution.

In fact, the Constitution does not cover all aspects of how Australia is governed. Many parts of our system of government, such as the Prime Minister and Cabinet, operate by tradition, similar to Britain. 

Political parties are also not defined by laws passed by the Australian Parliament.

diagram to help explain Are political parties mentioned or written in the Australian Constitution?