Background: Thymus and activation-regulated chemokine (CCL17) and macrophage-derived chemokine (CCL22) are known as important mediators in allergic inflammation. Recently many researchers have focused on these mediators, but the role of the serum CCL17 and CCL22 in allergic diseases in children are still controversial. The aims of this study were to compare serum levels of CCL17 and CCL22 between children with different manifestation of allergic diseases, such as bronchial asthma, allergic rhinitis and atopic dermatitis, to analyze relationship with blood eosinophil makers and to find clinical significance of these markers. Methods: A total of 49 children (14 bronchial asthma, 13 allergic rhinitis and 13 atopic dermatitis) and the 9 healthy control subjects were enrolled in this study. Clinical characteristics and serum chemokine (CCL17, CCL22) levels were analyzed. We examined whether serum levels of CCL17 and CCL22 would be related to serum immunoglobulin E levels, blood eosinophils and serum eosinophil cationic protein concentrations. Results: Serum levels of CCL17 and CCL22 were significantly higher in children with bronchial asthma and atopic dermatitis than that in controls. Serum levels of CCL17 and CCL22 were significantly related to serum immunoglobulin E levels, blood eosinophil counts and serum eosinophil cationic protein concentrations with different strength in children with allergic diseases. Conclusion: Serum CCL17 and CCL22 may play a crucial role in the chronic allergic inflammatory process and can be used as inflammatory markers. These suggest that serum CCL17 and CCL22 might be involved in the pathophysiology of allergic diseases in children.