A probable neurovisceral lysosomal storage disease is reported, for the first time, in immature red and grey kangaroos (Macropus rufus and M. giganteus). Foamy, pale eosinophilic, periodic acid-Schiff positive, intracytoplasmic material was stored in the liver, lymphoid tissue, kidney, adrenal gland, stomach, blood vessels and central nervous system. Extensive Wallerian-type degeneration was present in the central nervous system. Electron microscopic study of one animal revealed electron dense, cytoplasmic lamellar bodies in neurons and foamy visceral cells. The disease differs from other reported storage diseases in the distribution and nature of the lesions.