Chaihu Guizhi Decoction is an excellent prescription of ZHANG Zhongjing;however,nowadays the application of Chaihu Guizhi Decoction is primarily derived from the text.The xiang thinking is the source of traditional Chinese medicine thinking.Understanding Chaihu Guizhi Decoction from the xiang thinking,it is easy to perceive the true meaning of ZHANG Zhongjing,and grasp the location of the disease and the patient's overall qi,so as to make better use of this formula.This article discusses the understanding of Chaihu Guizhi Decoction from five perspectives:firstly,it gives an overview of the xiang thinking,pointing out the source and essential value of the xiang thinking;secondly,it analyses the disease position and the patient's qi of Chaihu Guizhi Decoction under the perspective of the xiang thinking as a whole;thirdly,it discusses the disease position and the patient's qi of the original text of Chaihu Guizhi Decoction from the xiang thinking;fourthly,it discusses how to understand the principle of formula formation and the main and minor parts of Chaihu Guizhi Decoction by xiang thinking;finally,it analyses the primary medicines in Chaihu Guizhi Decoction by using xiang thinking based on the records of Shennong Bencao Jing.Based on these five points,we hope to reveal the traditional Chinese medicine thinking behind Chaihu Guizhi Decoction,and provide new ideas for the clinical application of Chaihu Guizhi Decoction.