Atopic dermatitis (AD) is a prevalent condition associated with stress. However, epidemiological data on the impact of both common and severe childhood stressors are limited. This study aimed to evaluate the impact of stressful life events on AD activity and severity throughout early childhood. We conducted a longitudinal cohort study of 13,972 children aged 1-8.5 years from the Avon Longitudinal Study of Parents and Children. Responses to a standardized stressful life event scale were linked to repeated measures of annual AD period prevalence and severity. After adjusting for potential confounders, we found that for each SD increase in stressful life events, there was a small increased risk of concurrent AD activity (OR = 1.04, 95% confidence interval = 1.01-1.07), which was higher for moderate-to-severe AD (OR = 1.13, 95% confidence interval = 1.03-1.23) and for a cumulative measure of stressful events across childhood (OR = 1.11, 95% confidence interval = 1.07-1.16). The association was driven by common stressful life events which were perceived as more impactful to individual children such as starting a new school or having a new baby sibling, than severe adverse childhood events such as being separated from a parent or abused. These results may help provide anticipatory guidance to families.