There were some similarities on the basic level in that both instances in Australia and 1930s and 40s Europe did commit widespread genocide, justified by white supremacist feelings and policies and motivated by the identity of the victims. Both instances of genocide represented official government policies that were widely supported by the populations in those countries. But this is about where the similarities stop.
Being Jewish had to be legally defined by the Nazi regime, since Judaism is a religion and anyone can become a Jew, whereas the aboriginal peoples of Australia were born into their identity, and were also simpler for the British and Australian governments to single out. The campaign against the aborigines involved indirect methods of killing such as the introduction (both intentional and unintentional) of diseases such as small pox, which accounted for most of the deaths, over a long period of time while the Holocaust constructed and used a machinery of death in the concentration camps which took place in a concentrated span of only 8 years.