Sanguinaria canadensis, bloodroot, is a perennial, herbaceous flowering plant native to eastern North America. It is the only species in the genus Sanguinaria, included in the poppy family Papaveraceae, and is most closely related to Eomecon of eastern Asia.

Sanguinaria canadensis is sometimes known as Canada puccoon, bloodwort, redroot, red puccoon, and black paste. Plants are variable in leaf and flower shape, and have been separated as a different subspecies due to these variable shapes, indicating a highly variable species.

In bloodroot, the juice is red and poisonous. Products made from sanguinaria extracts, such as black salve, are escharotic and can cause permanent disfiguring scarring. Although preliminary studies have suggested that sanguinaria may have potential applications in cancer therapy, clinical studies are lacking, and its use is not recommended.