張元素，字潔古，金代易州（河北易水）人，他學識淵博，臨證經驗豐富，善於化裁古方。他建立了以臟腑辨證為核心的臨床證治體系，創新了用藥理論，在金元醫學中開創了新局面，對後世醫學有重大影響。「歸經」是我國歷代醫家經過長期醫療實踐，不斷探索、歸納、總結而形成和發展起來的中藥藥性理論之一，用以反映中藥作用於人體部位的一種性能。歸經的臨床意義，主要是進一步完善了中藥的性能理論，最重要的是增強了臨床用藥的準確性；「引經」是建立在歸經基礎上的，張元素完成了歸經、引經理論的內在理路模式，本文旨在討論張元素歸經、引經理論的特色。Zhang Yuansu, styled Jiegu, was born in Yizhou (now Yi River County, Hebei) in the Jin Dynasty. Being a knowledgeable man of great attainments in several fields, he had rich clinical experience and was good at adapting methods of the past to the present use. He established the organ-centered clinical treatment system and innovative medication theory, starting a new stage in the medicine of Jin and Yuan Dynasty, which had a significant impact on later medicine. Channel entry (gui jing) is one of the properties attributed to Chinese medicinals. Channel entry theory is the product of exploration and development by generations practicing physicians in China and that reflects the effects of Chinese medicinals on the human body. Clinically, channel entry theory further completes the body of theory concerning medicinal properties, yet its greatest significance is that it enhances the accuracy of clinical application. Channel conduction (yin jing) is based on the theory of channel entry, the main difference between the two being that the theory of channel entry applies to single medicinals, while channel conduction applies to combinations. Zhang completed the logic of the theory of channel entry and the medicinal conduction. This paper aims to discuss the features of these two theories.