Purpose: Vitamin D levels are known to be associated with development of allergic diseases. However, existing data are controversial. The aim of this study was to investigate whether vitamin D levels are associated with food sensitization (FS) in young children with atopic dermatitis (AD). Methods: We performed a medical record review of all patients under 2 years presenting to pediatric allergic clinic in Hallym University Sacred Heart Hospital for atopic dermatitis between March 1, 2012 and February 28, 2013. Serum 25-hydroxyvitamin D (25(OH)D) levels and six specific immunoglobulin E (IgE) to common food allergens were measured in 132 young children with AD. We defined vitamin D insufficiency was 25(OH)D <30 ng/mL, and FS as specific IgE ≥0.35 IU/mL to any of six common food allergens. Associations between serum 25(OH)D levels and FS were examined by using multiple logistic regression, adjusting for potential risk and confounding factors. Results: The mean age was 10.1 months. Among the 132 children with AD, 65.9% had FS. In this group, there was a negative correlation between 25(OH)D levels and serum eosinophil percentage (correlation coefficient [r]=.0.335, P<0.01), but not correlated with serum total IgE levels. Children with vitamin D insufficiency were more likely to have FS (adjusted odds ratio, 17.1; 95% confidence interval, 1.36 to 215; P=0.028) than those with adequate vitamin D levels. Conclusion: Vitamin D insufficiency is associated with FS in young children with AD. Further research is needed to confirm these findings. (Allergy Asthma Respir Dis 2013;1:211-215)