Strzyga is usually a female demon in Slavic mythology, which stems from the mythological Strix of Ancient Rome and Ancient Greece. The demon is similar to a vampire, and is predominantly found in Polish and Silesian folklore.

The strix, in the mythology of classical antiquity, was a bird of ill omen, the product of metamorphosis, that fed on human flesh and blood. It also referred to witches and related malevolent folkloric beings.