Purpose : The objective of present study is to detect the effect of Sopungsan aqueous extracts (SPS) on the passive cutaneous anaphylaxis (PCA; type I allergic dermatitis) Method : 500, 250 and 125mg/kg of SPS were orally administered 12 hr-interval before antigen challenge (total 4 times administered). PCA reactions were induced using rat anti-ovalbumin (OVA) serum contain IgE (titer 1:32) as sensitization and OVA as antigen challenge. 30 min after antigen challenge, the diameter of blue-dye spots (evans blue) and leaked amount of dye were observed with histology and histomorphometry at the PCA induced sites. In addition, serum total IgE and histamine levels were also observed by ELISA, respectively. The effects of SPS were compared with dexamethasone 1mg/kg treated rats in the present study. Results : As results of PCA reaction, vasodilation related increase of diameter of blue-dye spot and amount of leaked dye were observed with swelling and edematous changes in the dermis of PCA induced sites. However, these changes on PCA reactions were dramatically and dose-dependently decreased by treatment of SPS as compared with vehicle control. In addition, serum elevations of IgE and histamine were also dose-dependently inhibited by treatment of SPS as compared with vehicle control respectively. The effects of SPS 500mg/kg were similar to that of dexamethasone 1mg/kg in the present study. Conclusion : Base on the results of the present study, it is concluded that SPS has favorable effect on the PCA-induced allergic dermatitis, and SPS 500mg/kg showed similar favorable effects as compared with dexamethasone 1mg/kg. The present findings demonstrate that SPS can be effective for the prevention and treatment of allergic dermatitis.