Yonne is a department in the centre of France, in the Bourgogne-Franche-Comté region. The largest city in the department, and its prefecture (capital), is Auxerre.

The department is named after the Yonne river, a tributary of the Seine, that flows through the department. The Celts name of the river was Ica-onna (Latin: Icauna) and from this name come the name of the river and of the people living in the department: Icaunais.