Objectives : In this study, Samhwangsaejaegami extract was tested to prove its anti-atopic dermatitis effect on NC/Nga mice. Methods : In order to evaluate the external use effects of Samhwangsaejae extract on anti-atopic dermatitis, the expression of filaggrin, serine palmitoyltransferase(SPT), and COX-2 were analyzed. In vivo study, clinical skin severity score, IgE, IL-4, IL-5 and IL-6 level were analyzed through NC/Nga atopic mice model after 12 weeks external treatment. Results : In vitro study results showed the reduction in the expression of filaggrin, SPT, and COX-2. In vivo study results demonstrated the significant reduction in clinical skin severity score, IgE, IL-4, IL-5, IL-6 expression level. Conclusions : These results showed Samhwangsaejaegami extract can be a promising candidate for anti-atopic dermatitis treatment.