Background : Atopic Dermatitis is a chronic and recurrent skin disease. it is characterized as itch-scratch cycle and topical or systemic use of corticosteroids is required in western medicine. Though its effects on major symptoms are impressive, these treatments are prone to several side effects and tend to recur after months or years. So potential treatments have been actively studied in Estern medicine, especially Sasang constitutional therapy, which has fewer side effects. Objectives : The purpose of this study was to examine the effect of Sasang constitutional therapy on treating severe adult Atopic Dermatitis and preventing its recurrent symptoms. Methods : fifteen patients who had severe adult Atopic Dermatitis attended treatment of Sasang constitutional therapy and were followed up for one year. An oriental internal specialist first isolated Sasang constitution and a distinctive body type. Grading of Atopic dermatitis was measured by the guidelines offered by Rajka G. and Langeland T. Results : After treatment with Sasang constitutional therapy, the patients symptoms were improved and the mean Rajka and Langeland score reduced significantly from $7.73{pm}0.79;to;3.4{pm}10.91$. During the follow-up period of one year, the mean Rajka and Langeland score was $2.72{pm}2.06$ which was lower than last treatment. Conclusions : The results of this study support Sasang constitutional therapy as an effective therapy for severe adult Atopic Dermatitis. Follow up data suggest that this Eastern medical approach is of greater clinical value than the western medical approach in the long term.