We investigated the inhibitory effect of an oral administration of a Sophora flavescens Aiton ethanol extract (SFE) on the development of atopic dermatitis (AD) by using NC/Nga model mice. The induction of atopic dermatitis-like lesion was conducted by the removal of the back hairs and topical application of a mite antigen (Dermatophagoides farinae, Df) on to the back skin twice a week for 8 weeks. SFE was orally administered at a different doses (100-400 mg/kg). Atopic dermatitis-like skin lesions were evaluated by dermatitis scores, skin histology and immunological parameters (serum levels of IgE, TARC/CCL17, MDC/CCL22, and CTACK/CCL27). Oral administration of SFE significantly inhibited the clinical sign of Df-induced atopic dermatitis, including dermatitis score and leukocyte infiltration. Moreover, SFE suppressed significantly the serum IgE and Th2 chemokine (TARC/CCL17, MDC/CCL22, and CTACK/CCL27) levels in a concentration dependent manner. These results suggest that oral administration of SFE could reduce significantly the clinical signs and Th2 chemokines in Df-induced atopic dermatitis model mice. Therefore, SFE may be effective substances for the management of AD in human.