Debated. A life-sized red kangaroo was painted in a Kimberley rock shelter, but the page does not settle it as Australia's oldest art.
The painting is in Balanggarra Country, in the north-eastern Kimberley of Western Australia. It is about 2 metres long and made in red ochre. Wasp nests under and over the paint were dated to between about 17,500 and 17,100 years ago, so the kangaroo is put at about 17,300 years old. The same project looked at other animal paintings in eight shelters there.
The page first calls this the oldest dated painting in an Australian rock shelter, then says older dated rock art is already known, including a drawing about 28,000 years old.
https://www.ancient-origins.net/news-history-archaeology/kangaroo-painting-0014969