Gianysada (Greek: Γιανυσάδα, also Γιαννισάδα - Giannisada) is the southernmost island of the small Dionysades group of islands off Sitia on the northeast coast of Crete. The group also includes Dragonada, Paximada, and Paximadaki. Administratively this group comes within the Sitia municipality in Lasithi.
The Dionysades were once a place of worship of the ancient Greek god Dionysus. Archaeologists have found artefacts on this island group, from ancient and early Christian eras, indicating that the islands may have been inhabited in the past.