Objectives : Yiemyo-San(二妙散) is a basic oriental medicinal prescription used in basically musculoskeletal pain. Way down to posterity, Yiemyo-San has been combined with various prescriptions to treat a variety of diseases. the purpose of In this study is to investigate indications and etiology of indication using Yiemyo-San. Methodes : For prescriptions combining Yiemyo-San in Dongyeubogam(東醫寶鑑), the name of prescriptions, configuration herbs and indication were investigated and prescriptions were classified according to etiology of indication. Results : the numbers of prescriptions combining Yiemyo-San in Dongyeubogam were 45. Yiemyo-San was used frequently in musculoskeletal disease such as beriberi, amyotrophy, gout and arthritis(36%). In addition, it was applied to an internal diseases, ENT diseases and headache. it was used frequently in pathological condition due to supyeol(濕熱)(45%). Yiemyo-San was combined with various prescriptions as a primary prescription at 51% and as a secondary prescription at 49%. Conclusions : When Yiemyo-San is combined with other prescription, it may be used in various disease as well as musculoskeletal disease due to supyeol. combined with various prescriptions as a primary prescription at 51% and as a secondary prescription at 49%. Conclusions : When Yiemyo-San is combined with other prescription, it may be used in various disease as well as musculoskeletal disease due to supyeol.