Australovenator is based on AODL 604 (affectionately named “Banjo”) a partial skeleton including a left dentary, teeth, partial forelimbs and hindlimbs, a partial right ilium, ribs, and gastralia. Australovenator was described in 2009 by Scott Hocknull and colleagues. The type species is A. wintonensis, in reference to nearby Winton. A phylogenetic analysis found Australovenator to be an allosauroid carnosaurian, with similarities to Fukuiraptor and carcharodontosaurids. In the initial analysis, it was shown to be the sister taxon of the Carcharodontosauridae. More detailed studies found that it formed a clade with several other carcharodontosaurid-like allosaurs, the Neovenatoridae.
The ankles of Australovenator and Fukuiraptor are similar to the Australian talus bone known as NMVP 150070 that had previously been identified as belonging to Allosaurus sp., and it is likely that this bone represents Australovenator or a close relative of it.
AODL 604 was found about 60 kilometres (37 mi) northwest of Winton, near Elderslie Station. It was recovered from the lower part of the Winton Formation, dated to the latest Albian. AODL 604 was found in a clay layer between sandstone layers, interpreted as an oxbow lake, or billabong, deposit. Also found at the site were the type specimen of the sauropod Diamantinasaurus, bivalves, fish, turtles, crocodilians, and plant fossils. The Winton Formation had a faunal assemblage including bivalves, gastropods, insects, the lungfish Metaceratodus, turtles, the crocodilian Isisfordia, pterosaurs, and several types of dinosaurs, such as the sauropods Diamantinasaurus and Wintonotitan, and unnamed ankylosaurians and hypsilophodonts. Plants known from the formation include ferns, ginkgoes, gymnosperms, and angiosperms. Australovenator was a medium-sized allosauroid. According to Hocknull, it was 2 metres (6.6 ft) tall at the hip and 6 metres (20 ft) long. Only a single individual has been uncovered so scientists can't be certain if the skeleton is an adult or juvenile. Because it was a lightweight predator, he coined it as the “cheetah of its time”. Like other carnosaurians, Australovenator would have been a bipedal carnivore.
Australovenator made an appearance in the famous documentary Walking with Dinosaurs (however, it was called "Dwarf Allosaur" because scientists hadn't come up with a name for it yet), where it attacked a small herd of Leaellynasaura and killed its female matriarch. It also harrassed a herd of the large hadrosaurid Muttaburrasaurus and scavenged a carcass from one of them.The Australovenator nicknamed 'Banjo' appears in both fossil and live form in the documentary Australia: The First 4.5 Billion Years.