Hulitherium lived in montane rain forests and was proposed in its initial description to have fed on bamboo, as a kind-of marsupial analogue of the giant panda. It was one of New Guinea's largest mammals, standing at 1 m (3 ft) tall, close to 2 m (6 ft) long, and with an estimated weight of 75–200 kilograms (165–441 lb). Flannery and Plane (1986) suggested that because little had changed since the Late Pleistocene, humans may have been the major factor that led to its extinction. The head of the femur lies directly above the shaft, which along with the morphology of the humerus-ulnar joint, suggests that Hulitherium reared up on its hind legs to feed. Dental microwear results support that Hulitherium was a browser that fed on soft plant material, rather than on fibrous bamboo.