Prunus spinosa, called blackthorn or sloe, is a species of flowering plant in the rose family Rosaceae. The species is native to Europe, western Asia, and regionally in northwest Africa. It is locally naturalized in New Zealand, Tasmania, and the Pacific Northwest and New England regions of the United States.

Rosaceae, the rose family, is a medium-sized family of flowering plants that includes 4,828 known species in 91 genera.