Abstract: When he evaluated the style of the poets of Yuanhe School in his book The Supplement of Tang Dynasty's History,LI Zao said that they imitated the freely flowing characteristics from ZHANG Ji when they are writing Gexing.Based on the fruits of predecessors's studies,we can give a definition to Gexing from the aspect of forms and tones,thus analyze the content and artistic characteristics of ZHANG Ji's Gexing.