AIM: There is a paucity of population-based studies regarding the spectrum of paediatric head injury from mild through serious to fatal paediatric head injury. The aims of the present study were to determine the incidence, demographics and outcome of significant head injury in a state-wide population of children aged 0-15 years. A secondary aim was to determine if any serious head injuries were being missed under the current management protocols of the state-wide trauma system. METHODS: A retrospective review of significant head injury in all paediatric patients over a period of 2 years was undertaken. Data were collected from the Victorian State Trauma Outcome Registry and Monitoring database, the Victorian Emergency Minimum Dataset and from the Victorian Institute of Forensic Medicine. RESULTS: The incidence of paediatric head injury in Victoria over the 2-year period was 765 per 100000 per year. The incidence of admitted head injuries was 75 per 100000 per year and the incidence of significant head injury was seven per 100000 or 151 children. Forty-one per cent of these injuries required surgical intervention. Mortality was 1.6 children per 100000. All patients who died presented with a Glasgow Coma Score (GCS) of 3 and had multiple other risk factors. There were no deaths in patients discharged from hospital. Demographic and clinical factors associated with higher mortality and morbidity was determined. CONCLUSION: The incidence of significant paediatric head injury was low. Deaths occurred early and were always associated with significant early clinical features of severe head injury. This highlights the importance of strategies for the prevention of head injuries. There appeared to be no serious head injuries missed during the study period.