Excessive fire due to yin deficiency belongs to deficiency fire, which is mostly caused by deficiency of essence and blood, serious injury of body fluid due to yin deficiency and hyperactivity of yang due to yin deficiency, so deficiency heat and deficiency fire are endogenous. Its clinical fiery signs are often concentrated in a certain part of the body. For example, toothache, sore throat, dry lips, hot flashes caused by bone steaming, and zygomatic redness caused by yin deficiency are all caused by inflammation of deficiency fire. Yin deficiency and excessive fire are the diagnosis of syndrome differentiation in traditional Chinese medicine, and Chinese medicine nourishes yin, clears heat and regulates. Chinese patent medicines, Kuntai Capsule and Baizhi Dihuang Pill, are suitable for yin deficiency and hyperactivity of fire.