This article discusses the treatment of arm lymphedema in breast cancer with traditional Chinese medicine. It is believed that the pathogenesis of arm lymphedema following breast cancer surgery is that " Unsmooth Blood Circulation Results in Water Retention", " Water" is the cause of " Blood". " Unsmooth Blood Circulation" is the middle link of causing edema, and ”Water Retention" is the pathological product of ” Unsmooth Blood Circulation". The root cause of " Unsmooth Blood Circulation" and ” Water Retention" lies in disorder of Qi activit...