Atopic dermatitis (AD) is a chronic inflammatory skin disease that induces changes in various inflammatory skin cells. The prevalence of AD is as high as 18% in some regions of the world, and is steadily rising. However, the pathophysiology of AD is poorly understood. To identify the proteins involved in AD pathogenesis, a comparative proteomic analysis of protein expression in peripheral blood mononuclear cells isolated from AD patients and healthy donors was conducted. Significant changes were observed in the expressions of fourteen proteins, including the vinculin, PITPNB, and Filamin A proteins. Among the proteins, alpha-SNAP and FLNA decreased significantly, and PITPNB increased significantly in AD patients compared with control subjects; these findings were further confirmed by real-time PCR and Western blot analysis. The comparative proteome data may provide a valuable clue to further understand AD pathogenesis, and several differentially regulated proteins may be used as biomarkers for diagnosis and as target proteins for the development of novel drugs.