Objectives The purpose of this study is to investigate the effect of Li Zhong Tang(LZH-T) on atopic dermatitis by using NC/Nga atopic dermatitis mouse. Methods First, in vitro, we isolated B cells from NC/Nga mouse which induced atopic dermatitis-like skin for 18 weeks. We analyzed FACS by intracellular staining of $IFN-{gamma}$, GATA-3+ and also analyzed cytokines by using real-time PCR. Secondly, in vivo, after administration of LZH-T to the 12 weeks old mouse with atopic dermatitis. We analyzed serum IgE, $IFN-{gamma}$ level and observed the changes of activated cell. Results In vitro, LZH-T decreased the levels of CD4+/$IFN-{gamma}$ and increased the levels of CD4+/GATA3+. In vivo, serum IgE levels were decreased and $IFN-{gamma}$ levels were increased in LZH-T group compared to the control group. In PBMCs, the percentage of activated cell - granulocytes, CD3+, CD3+CD4+, B220+CD23+, and CCR3+ were decreased and CD19+, CD3+CD8+ were increased in LZH-T group compared to the control group. Conclusions This study demonstrates immunological activity of GPJST on atopic dermatitis-like model mice.