Objectives : Betula platyphylla var. japonica extract (BPE) was used to determine the modulation of cytokine secretion, the activation of inflammatory and allergic factor and the inhibition of gene expression. Inflammatory and allergic cytokines as IL-$1{eta}$, IL-2, IL-4, IL-5, IL-6, IL-8, TNF-${alpha}$, NO and COX-2 were measured to use effectively on improvement or treatment of atopic dermatitis. Methods : We used NC/Nga mouse induced by atopic dermatitis to observe the effects of BPE on the weight, water and feed, blood test, weight of organs, histological change, total IgE and histological change of main organs. Results : BPE is effective on anti-inflammatory and allergic reaction. However, further study is needed to prove which component of BPE indicates effective pharmacological action. Conclusions : The above results suggest that Phellinus igniarius Quel extract could be applicable for improvement of several skin functions.