Purpose: Patients with atopic dermatitis (AD) experience a chronic relentless course which may affect emotional and behavioral problems. Moreover, AD could affect serious psychosocial problems due to its disfiguring skin conditions, particularly in adolescents who are under various stresses. The aim of this study was to investigate behavioral problems in children and adolescents with AD and to identify associated clinical factors. Methods: A total of 69 subjects with AD were enrolled in this study. The severity of AD was assessed using the SCORAD (Scoring of Atopic Dermatitis) index and divided into 2 groups: mild-to-moderate and severe groups. Behavioral problems were assessed by using the Korean Child Behavior Checklist (K-CBCL). Results: The severe AD group had higher total behavior problem scores and internalizing scores than the mild-to-moderate group. Social problem and attention problem scores were slightly higher in the severe AD group than in the mild-to-moderate AD group. The DSM (diagnostic and statistical manual of mental disorders)-anxiety, obsessive compulsive problems, and sluggish cognitive tempo problems were more frequently observed in the severe AD group. Longer disease duration was an independent risk factor of internalizing problems in subjects with AD. Conclusion This study showed that subjects with severe AD had higher total behavioral problem scores, particularly internalizing scales. Their behavioral problems may have poor compliance and consequently poor outcomes as well. Clinicians should be aware that children and adolescents with severe AD have more behavioral problems and that an interdisciplinary approach with medical and psychological supports is necessary for proper management.