Quantassaurus is a genus of dinosaur belonging to the group Ornithopoda. It lived during the Early Cretaceous period, approximately 115 million years ago. The first fossils of Quantassaurus were discovered in the 1970s in the Quantam Creek Formation in New South Wales, Australia. Since then, paleontologists have uncovered additional remains, contributing to our understanding of this unique dinosaur.

Quantassaurus was a relatively small dinosaur, estimated to be around 6.5 to 8 feet (2 to 2.5 meters) in length. Its body was characterized by a bipedal stance, walking on its powerful hind legs. While some details of its anatomy remain elusive due to incomplete fossil remains, it is believed to have had a slender build and a long tail, typical of ornithopod dinosaurs.

Qantassaurus was named after Australia´s national airline, Qantas. Qantassaurus was a bipedal herbivore, it had a short deep head, five-fingered hands with four-toed feet and a tail as long as the head and body combined.

Qantassaurus was one of the first hypsilophodontids to be discovered. It also co-existed with others of the same genus, which has made it more difficult for scientists do differentiate qantassaurus´s bones from for example leaellynasaura´s bones.