關於〈中庸〉「中和」之詮釋，在宋朝之後成為儒家重要的討論議題。東漢鄭玄是最早註解〈中庸〉的經師，但他對於「中和」的說法卻一直不受重視。本文經由分析鄭玄以「天地覆載」詮釋「中和」的說法，歸納出：「中」是內在之「位域」，此位域能含容、節制人的情性，使之「發而皆中節」，達到「和」之狀態。「致中和」，則與天地合德，而能化育萬物。「中和」平淡、無為，既能成己，又能成物。「至誠」是達致中和之引使。而「禮樂」符合天地之道，是使人和社會達致中和的最佳方式，故治國不能不為禮樂。

＂ZhongHe＂, as a specific phrase with concise explanation originated from the chapter of ＂ZhongYong＂ in ＂Li Ji＂, has become one of the most essential issues amongst Confucianists and the researchers since Song dynasty. Zheng, Xuan, a maestro of Confucianism who was born in Eastern Han dynasty and first annotated ＂Li Ji＂, his viewpoints are highly contributive to posterity for understanding the thought of ＂ZhongYong＂, but the scholars have never been placed importance on his unique and inspiring interpretation of ＂ZhongHe＂. This article aims at analyzing how Zheng, Xuan adopted the concept of ＂Covering and Holding like heaven and earth＂ to interpret the significance of ＂ZhongHe＂, and coming to a conclusion: ＂Zhong＂ refers to an internal, spiritual and dimensional state of human which is capable of holding and restraining human's sentiments and characters, so as to conduct them present within reasonable and moderate limits, even to an ideal extent for so-called ＂He＂. If a man could achieve the state of ＂ZhongHe＂, he could dedicate the world with nourishment and reformation, following the pattern and power as heaven and earth sustain and regulate the life of everything. The state of ＂ZhongHe＂ is moderate, WuWei (letting things act spontaneously by the light of moral affection), and accomplishing the best of oneself and world. ＂ZhiCheng＂ (Extreme Earnest) refers to human's inner motivity to achieve ＂ZhongHe＂, whereas ＂LiYue＂ (Rites and Musics) which echo the＂Dao＂ (principle) of heaven and earth, refers to outer best measures impact individuals and society to attain ＂ZhongHe＂, thus the kingcraft ought to take ＂LiYue＂ into acoount.