BACKGROUND: There has been little reported research into the effect of war on the behaviour and emotional well-being of pre-school children. AIMS: To investigate the relationship between exposure to war trauma and behavioural and emotional problems among pre-school children. METHOD: A total of 309 children aged 3-6 years were selected from kindergartens in the Gaza Strip, and were assessed by parental reports in regard to their exposure to war trauma, using the Gaza Traumatic Checklist, and their behavioural and emotional problems, using the Behaviour Checklist (BCL) and the Strengths and Difficulties Questionnaire (SDQ). RESULTS: Pre-school children were exposed to a wide range of traumatic events. The total number of traumatic events independently predicted total BCL and SDQ scores. Exposure to day raids and shelling of the children's houses by tanks were significantly associated with total behavioural and emotional problems scores. CONCLUSIONS: Direct and non-direct exposure to war trauma increases the risk of behavioural and emotional problems among pre-school children, which may present as non-specific psychopatholo