Threatened fauna of Australia are those species and subspecies of birds, fish, frogs, insects, mammals, molluscs, crustaceans, and reptiles to be found in Australia that are in danger of becoming extinct. This article lists species classified as threatened species under the Commonwealth Environment Protection and Biodiversity Conservation Act 1999.

Dryococelus australis, commonly known as the Lord Howe Island stick insect or tree lobster, is a species of stick insect that lives on the Lord Howe Island Group. It is the only member of the monotypic genus Dryococelus. Thought to be extinct by 1920, it was rediscovered in 2001. It is extirpated in its largest former habitat, Lord Howe Island, and has been called "the rarest insect in the world", as the rediscovered population consisted of 24 individuals living on the small islet of Ball's Pyramid.