Objectives : The water extract of Hwangnyeonhaedok-tang (HHT), composed of the Scutellariae Radix, Coptidis Rhizoma, Phellodendri Cortex and Gardeniae Fructus has been traditionally used to treat fever, inflammation, gastritis and hypertension in east asia. However, little is known about the ameliorative effects of HHT on atopic dermatitis. Therefore, the purpose of this study was to investigate the therapeutic effect of HHT on atopic dermatitis Methods : We investigated the inhibitory effects of HHT on the production of proinflammatory cytokines in rat peritoneal mast cells (RPMCs), on the scratching behavior in ICR mice, and on atopic dermatitis symptoms in 2,4-dinitrofluorobenzene (DNFB)-induced atopic dermatitis-like model hairless mice. Results : Levels of TNF-${alpha}$ and IL-$1{eta}$ increased by PMA plus A23187 co-treatment were significantly inhibited by HHT in a dose-dependent manner. HHT also inhibited the histamine release from RPMCs stimulated by compound 48/80, which promotes histamine release. The oral administration of HHT reduced the scratching behavior induced by compound 48/80 and histamine in ICR mice. Furthermore, the intradermal treatment of HHT reduced the ear edema, skin lesions, and atopic molecular marker (IgE and IL-4) in DNFB-induced atopic dermatitis model mice. Conclusions : These results suggest that HHT may be used as a potential treatment for AD as a prescription for treatment of atopic dermatitis.