Aims: To document gastroenteritis hospitalisations of the 1995-96 cohort of infants born in Western Australia to mid-2002, and to assess factors associated with their hospitalisations and readmissions. Methods: Retrospective analysis of the State's hospitalisation data, Midwives' Notification of Births data, the Australian Bureau of Statistics mortality data and clinical and demographic information. Results: Aboriginal infants were hospitalised for gastroenteritis eight times more frequently than their nonAboriginal peers, and were readmitted more frequently and sooner for diarrhoeal illnesses than the other group. They also stayed in hospital for twice as long and many Aboriginal patients were hospitalised on numerous occasions. Hospitalisation rates were higher in remote areas and were significantly associated with co-morbidities such as undernutrition, anaemia, co-existing infections, and intestinal carbohydrate intolerance. Conclusions: Gastroenteritis is very prevalent in Australian Aboriginal infants and children and is a major cause of their hospitalisation in Western Australia. It is often associated with undernutrition, anaemia, intestinal parasitic infestations, other infections, intestinal carbohydrate intolerance, and, in some instances, with low birth weight. This is often due to unhygienic living conditions and behaviours and presents major challenges to public health, health promotion, and clinical personnel, particularly paediatric services. Childhood diarrhoeal diseases occur commonly in other indigenous groups but have not received the attention that they deserve.