Abstract：This paper analyzes and summaries the key points of syndrome differentiation and treatment ideas of Prof. HU Xishu using the four classical prescriptions which are Linggui Zhugan tang，Wuling powder，Zhenwu tang and Zexie tang， based on his theory of “differentiating syndromes through prescriptions” and combined with the clinical medical case of using the above four classical prescriptions to treat fluid retention- induced vertigo. After analysis，it can be concluded that Linggui Zhugan tang，Wuling powder，Zhenwu tang and Zexie tang all can be used to treat fluid retention-induced vertigo， but the corresponding classical prescriptions in clinical practice should be selected according to different pathogenesis and syndrome types shown in the these prescriptions： Wuling powder is used to treat exterior deficiency of greater yang and interior fluid retention；Zexie tang is used to treat fluid retention below the heart going upward into the head and the face； Zhenwu tang is used to treat combined diseases of lesser yin and greater yin and edema due to yang deficiency； Linggui Zhugan tang is used to treat the spleen yang failing in transportation and the internal generation of phlegm rheum and fluid retention.