This paper examined the history of snakes as a source of drugs from the Han to the Song Dynasties. Snake products, for medicinal purposes, were not widely used in the Han, Wei and Jin Dynasties out of worship and fear of snakes. The source of snake products taken for medical purposes might be partly because local people ate snakes in the South area. Palace snakes and pit viper products were taken as drugs in the Tang Dynasty for the treatment of leprosy and ulcers of the female external genitals. Zaocysdhumnades were seldom used as medicine because they were not recorded in medical documents in the Tang Dynasty, but only seen in some notes. They were widely used in medical practice in the late Tang and the early Song Dynasties and were formally recorded in medical documents for the diseases caused by Wind. Their effectiveness, rarity, high value and toxicity contraindication were repeatedly stressed while palace snakes and pit vipers were seldom mentioned and used.