AIM: Exposure to a large natural disaster can lead to behavioural disturbances, developmental delay and anxiety among young children. Although most children are resilient, some will develop mental health problems. Major earthquakes occurred in Canterbury, New Zealand, in September 2010 and February 2011. A community screening tool assessing behavioural and emotional problems in children, the Strengths and Difficulties Questionnaire, has been reported by parents (SDQ-P) and teachers (SDQ-T) of all 4-year-olds in the region since 2008. METHODS: Mean total and subtest scores for the SDQ-P and SDQ-T were compared across periods before, during and after the earthquakes in sequential population cohorts of children. Comparisons across the periods were made in relation to the proportions of children defined by New Zealand norms as ‘abnormal’. Results were also compared between zones considered to have been exposed to higher or lower impact from the earthquakes. RESULTS: Parent mean total SDQ scores did not change between periods before, during and after the earthquakes. Teacher mean SDQ total scores significantly reduced (improved) when compared between baseline and post-earthquake periods. Mean SDQ pro-social scores from both teachers and parents increased (strengthened) when compared between baseline and post-earthquake periods. Results did not significantly vary according to a measure of impact from the earthquakes. CONCLUSION: The main finding that a population-based measure of behavioural and emotional problems among children was not deleteriously impacted by the earthquakes is surprising and is not consistent with other research findings. Further work is needed to explore the health needs of children in Canterbury based on methodological improvements.