The New Holland Mouse (Pseudomys novaehollandiae) is a species of rodent in the family Muridae. It was first described by George Waterhouse in 1843. It vanished from view for over a century before its rediscovery in Ku-ring-gai Chase National Park north of Sydney in 1967. It is found only in south east Australia, within the states of New South Wales, Queensland, Victoria, and Tasmania.