水飞蓟属（学名：Silybum）是菊科下的一个属，为草本植物。该属共有2种，分布于欧洲、非洲和亚洲。

Silybum (milk thistle) is a genus of two species of thistles in the (daisy family). The plants are native to the Mediterranean regions of Europe, North Africa, and the Middle East. One species has been introduced elsewhere, including in North America. The name "milk thistle" derives from a feature of the leaves, which are prominently banded with splashes of white. Historically, these milky bands were said to be Mother Mary's milk, and this is the origin of another common name, St. Mary's thistle. The most widespread species is Silybum marianum.